Thermomechanical effect in molecular crystals: the role of halogen-bonding interactions

Mittapalli, S.; Perumalla, D.S.; Nanubolu, J.B.; Nangia, A.

doi:10.1107/S2052252517014658

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IUCrJ

Volume 4| Part 6| November 2017| Pages 812-823

ISSN: 2052-2525

https://doi.org/10.1107/S2052252517014658

CHEMISTRY | CRYSTENG

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Thermomechanical effect in molecular crystals: the role of halogen-bonding interactions

Sudhir Mittapalli,^a D. Sravanakumar Perumalla,^b Jagadeesh Babu Nanubolu ^c and Ashwini Nangia ^a,^d ^*

^aSchool of Chemistry, University of Hyderabad, Professor C. R. Rao Road, Gachibowli, Hyderabad 500 046, India, ^bDepartment of Inorganic and Physical Chemistry, Indian Institute of Science, Bengaluru 500 016, India, ^cCSIR-Indian Institute of Chemical Technology, Tarnaka, Hyderabad 500 007, India, and ^dCSIR-National Chemical Laboratory, Dr Homi Bhabha Road, Pune 411 008, India
^*Correspondence e-mail: ashwini.nangia@gmail.com

Edited by M. Eddaoudi, King Abdullah University, Saudi Arabia (Received 12 May 2017; accepted 10 October 2017; online 27 October 2017)

The design and synthesis of mechanically responsive materials is interesting because they are potential candidates to convert thermal energy into mechanical work. Reported in this paper are thermosalient effects in a series of halogen derivatives of salinazids. The chloro derivative, with higher electronegativity and a weaker inter-halogen bond strength (Cl⋯Cl) exhibits an excellent thermal response, whereas the response is weaker in the iodo derivative with stronger I⋯I halogen bonding. 3,5-Dichlorosalinazid (Compound-A) exists in three polymorphic forms, two room-temperature polymorphs (Forms I and II) and one high-temperature modification (Form III). The transformation of Form I to Form III upon heating at 328–333 K is a reversible thermosalient transition, whereas the transformation of Form II to Form III is irreversible and non-thermosalient. 3,5-Dibromo- (Compound-B) and 3-bromo-5-chloro- (Compound-C) salinazid are both dimorphic: the Form I to Form II transition in Compound-B is irreversible, whereas Compound-C shows a reversible thermosalient effect (362–365 K). In the case of 3,5-diiodosalinazid (Compound-D) and 3,5-difluorosalinazid (Compound-E), no phase transitions or thermal effects were observed. The thermosalient behaviour of these halosalinazid molecular crystals is understood from the anisotropy in the cell parameters (an increase in the a axis and a decrease in the b and c axes upon heating) and the sudden release of accumulated strain during the phase transition. The di-halogen salinazid derivatives (chlorine to iodine) show a decrease in thermal effects with an increase in halogen-bond strength. Interestingly, Compound-B shows solid-state photochromism in its polymorphs along with the thermosalient effect, wherein Form I is cyan and Form II is light orange.

Keywords: halogen bonds; hydrogen bonds; materials science; polymorphism; salinazid; crystal engineering; mechanochemistry; molecular crystals; materials modelling.

CCDC references: 1579384; 1548278; 1548279; 1548280; 1548281; 1548282; 1548283; 1548284; 1548285

1. Introduction

The development of mechanically responsive materials which respond to external stimuli such as heat, light and pressure is important because these materials are known to be self-actuating and energy-harvesting (Kim et al., 2013 ; Morimoto & Irie, 2010 ; McCrone, 1965 ; Panda et al., 2015 ). They have wide-ranging applications, such as artificial muscles and biomimetic and technomimetic materials (Cabane et al., 2012 ; Ikeda et al., 2007 ; Lehn, 2002 ; Mather, 2007 ; Rowan, 2009 ; Sagara & Kato, 2009 ; Sato, 2016 ; Takashima et al., 2012 ). The design of smart materials with reversibility, stability and controlled properties is challenging (Mao et al., 2016 ; Park et al., 2016 ). The properties of solid-state crystalline materials depend not only on the molecular functional groups but, more significantly, on the intermolecular interactions, hydrogen bonding and molecular packing in the crystal structure. The mobility of molecules in the solid state is limited and hence when an external stimulus is applied the molecules become activated and undergo a chemical reaction or polymorphic phase change along with mechanical movement, referred to as dynamic molecular crystals, or without movement (Lieberman et al., 2000 ; Naumov et al., 2015 ; Swapna et al., 2016 ; Sato, 2016). The dynamic behaviour of crystals towards applied heat (thermosalient effects; Lusi & Bernstein, 2013 ; Nath et al., 2014 ; Sahoo et al., 2013 ; Skoko et al., 2010 ; Takeda & Akutagawa, 2016 ) or light energy (photosalient effect; Medishetty et al., 2015 ) can occur with or without a change in the crystal morphology and packing of the molecules. The first reported example of the thermosalient effect was (phenylazophenyl)palladium hexafluoroacetylacetonate, an organometallic compound whose crystals were shown to jump/expand during phase transition (Etter & Siedle, 1983 ). Yao et al. (2014 ) reported the Ni complex [Ni^II(en)₃](ox) [en= ethylenediamine; ox = oxalate] with a reversible shape change and deformation of the crystals due to a 90° rotation of the oxalate anion during phase transition and anisotropy in the unit-cell parameters. Das et al. (2010 ) reported deformation of (S,S)-octa-3,5-diyn-2,7-diol crystals due to the anisotropy in the cell parameters and a change in the stacking angle from 54 to 51°. Panda et al. (2016 ) reported positive and negative thermal expansion in thermosalient N′-2-propylydene-4-hydroxybenzohydrazide crystals. There have been a few reports of dynamic organic molecular crystals exhibiting jumping, curling, rolling and explosion upon external stimulus (Kim et al., 2013; Koshima et al., 2009 ; Kumar et al., 2013 ; Baker, 2017 ; Uchida et al., 2008 ).

In the present investigation, a series of di-halosubstituted (Cl, Br, I and F) Schiff bases showing thermal responses and solid-state photochromism are reported. The dichloro- (Compound-A), dibromo- (Compound-B) and 3-bromo-5-chloro- (Compound-C) salinazid derivatives showed jumping/breaking/cracking of the crystals during phase transformation. Phase transformation with a change in Z′ from 1 to 2 was observed for Compound-B, with significant changes in the molecular conformation (dihedral angles), hydrogen bonding and crystal packing. Crystals of Compound-D and E (diiodo- and difluoro-salinazid) did not show any type of thermal response on heating. Chemical diagrams are shown in Scheme 1, and the 2-hydroxybenzylidene isonicotinohydrazide skeleton is referred to as salinazid.

2. Experimental

For the preparation of dichlorosalinazid Compound-A, (E)-N′-(3,5-dichloro-2-hydroxybenzylidene)isonicotinohydrazide, the conventional reaction with azeotropic removal of water (Safin et al., 2014 ) was followed. Isonicotinohydrazide (1 mmol, 137 mg) was dissolved in anisole (10 ml) in a 100 ml round-bottomed flask fitted with a Dean–Stark set up. 3,5-Dichlorosalicylaldehyde (1 mmol, 191 mg) was added to the solution. The reaction mixture turned light yellow (after 10 min) and it was refluxed for 4 h. The solution was concentrated by removing the solvent and was then washed with n-hexane 3–4 times to remove unwanted by-products. Light-cyan crystals of dichloro Compound-A were obtained in 80% yield. The same procedure was followed for the synthesis of Compounds-B, C, D and E, and their structures were confirmed by ¹H NMR and ¹³C NMR (Figs. S1a–S1h in the supporting information) and finally by single-crystal X-ray diffraction.

2.1. Compound-A

¹H NMR (400 MHz, d₆-DMSO, 298 K, δ in p.p.m., Fig. S1a): 12.73 (s, 1H), 12.30 (s, 1H), 8.82 (d, J = 2.4 Hz, 2H), 7.86 (d, J = 2.8 Hz, 2H), 7.73 (d, J = 2.56 Hz, 1H), 7.66 (d, J = 2.48 Hz, 1H), 7.45 (br, 1H).

¹³C NMR (400 MHz, d₆-DMSO, 298 K, δ in p.p.m., Fig. S1b): 166.7, 157.4, 155.6, 153.2, 153.1, 144.4, 135.6, 133.5, 128.2, 126.8 and 125.8.

FT–IR (KBr, cm⁻¹, Fig. S2a): 3193.3 (br, OH), 1677.8 (m, C=O), 1612.7 (m, C=N), 1555.6 (w), 1498.6 (w), 1451.7 (m), 1434.1 (w), 1349.4 (w), 1180 (m).

2.2. Compound-B

¹H NMR (400 MHz, d₆-DMSO, 298 K, δ in p.p.m., Fig. S1c): 12.78 (s, 1H), 12.53 (s, 1H), 8.82 (d, J = 5.6 Hz, 2H), 8.56 (s, 1H), 7.85 (t, J = 2.8 Hz, 4H).

¹³C NMR (400 MHz, d₆-DMSO, 298 K, δ in p.p.m., Fig. S1d): 162.1, 154.1, 150.9, 148.5, 139.7, 136.3, 132.6, 122.0, 121.3, 111.8 and 111.7.

FT–IR (KBr, cm⁻¹, Fig. S2b): 3149.7 (br, OH), 1685.3 (m, C=O), 1593.9 (m, C=N), 1549.5 (w), 1441.8 (w), 1370.3 (m), 1340.1 (w), 1269.1 (w), 1218.7 (m).

2.3. Compound-C

¹H NMR (400 MHz, d₆-DMSO, 298 K, δ in p.p.m., Fig. S1e): 12.76 (s, 1H), 12.50 (s, 1H), 8.83 (d, J = 6.0 Hz, 2H), 8.58 (s, 1H), 7.87 (d, J = 6 Hz, 2H), 7.78 (d, J = 3.2 Hz, 2H).

¹³C NMR (400 MHz, d₆-DMSO, 298 K, δ in p.p.m., Fig. S1f): 166.8, 158.5, 155.6, 153.3, 144.4, 138.5, 134.5, 128.6, 126.7, 125.4 and 116.1.

2.4. Compound-D

¹H NMR (400 MHz, d₆-DMSO, 298 K, δ in p.p.m., Fig. S2g): 12.77 (m, 2H), 8.83 (m, 2H), 8.47 (s, 1H), 8.08 (d, J = 1.2 Hz, 1H), 7.95 (s, 1H), 7.85 (t, J = 4.8 Hz, 2H).

2.5. Compound-E

¹H NMR (400 MHz, d₆-DMSO, 298 K, δ in p.p.m., Fig. S2h): 12.46 (s, 1H), 11.12 (s, 1H), 8.81 (d, J = 4.8 Hz, 2H), 8.69 (s, 1H), 7.85 (d, J = 4.8 Hz, 2H), 7.39 (m, 2H).

2.6. X-ray crystallography

X-ray reflections for Compounds-A (Form I and Form II), -B (Form I and Form II), -C (Form I), -D and -E were collected on a Bruker D8 Quest CCD diffractometer equipped with a graphite monochromator and an Mo Kα fine-focus sealed tube (λ = 0.71073 Å) at 298 K. High-temperature data for Compound-A Form III and Compound-C Form II were collected on a Bruker D8 Venture diffractometer at 338 and 368 K, respectively. Data reduction was performed using Bruker APEX2 software. Intensities were corrected for absorption using SADABS (Sheldrick, 1997a ) and the structures were solved and refined using SHELX97 (SMART 2000; Sheldrick, 1997b ). All non-H atoms were refined anisotropically. H atoms on hetero atoms were located from difference electron-density maps and all C-bound H atoms were fixed geometrically. ORTEP plots are shown in Fig. S3 in the supporting information. Hydrogen-bond geometries were determined using PLATON (Spek, 2002 ). X-Seed (Barbour, 1999 ) was used to prepare packing diagrams. The crystal structures have been deposited with the Cambridge Structural Database (CCDC Numbers 1548278–1548285). Compound-A Form I is reported in the CCDC as No. 824932.

2.7. Powder X-ray diffraction (PXRD)

Powder X-ray diffraction was recorded on Bruker D8 Advance diffractometer (Bruker AXS, Karlsruhe, Germany) using Cu Kα X-radiation (λ = 1.5406 Å) at 40 kV and 30 mA power. X-ray diffraction patterns were collected over the 2θ range 5–40° at a scan rate of 1° min⁻¹.

2.8. Infrared spectroscopy (IR)

A Nicolet 6700 FT–IR spectrometer with an NXR FT–Raman Module was used to record IR spectra. IR spectra were recorded on samples dispersed in KBr pellets.

2.9. Differential scanning calorimetry (DSC)

DSC was performed on a Mettler Toledo DSC 822e module. Samples were placed in crimped but vented aluminium sample pans. The typical sample size was 3–5 mg. The temperature range was 303–573 K at 20 K min⁻¹. Samples were purged by a stream of nitrogen flowing at 60 ml min⁻¹.

2.10. Thermogravimetric analysis (TGA)

TGA was carried out using a Mettler Toledo TGASDTA 851e operating with STAR^e software to detect solvates and thermal degradation. Accurately weighed (5–15 mg) samples were loaded in alumina crucibles and heated at a rate of 20 K min⁻¹ over a temperature range of 303 to 573 K under a nitrogen purge of 60 ml min⁻¹.

2.11. Hot-stage microscopy (HSM)

HSM was performed on a Wagner & Munz Polytherm A Hot Stage and Heiztisch microscope. A Moticam 1000 (1.3 MP) camera supported by software Motic Image Plus 2.0ML was used to record images and videos (Fig. S4 in the supporting information).

2.12. Computations

The stabilization energies of all complexes were computed using M062X/6-31g(d,p) (SDD for Br and I) (Zhao & Truhlar, 2008 ) in the GAUSSIAN09 package (Frisch et al., 2009 ). All energies are BSSE-corrected using the counterpoise method.

3. Results and discussion

The dichloro Compound-A was crystallized from methanol multiple times and finally provided diffraction-quality single crystals of Form I. Form II crystals were obtained from a methanol slurry after 1 d. The high-temperature polymorph Form III was isolated by heating and it is stable at high temperature (above 330 K, HT polymorph). Crystallization experiments on compounds-B, -C, -D and -E provided dimorphs of B and C, while D and E each gave a single-crystal form. Scheme 2 shows the thermal-induced and crystallization transformation for polymorphs of Compound-A and Scheme 3 shows thermosalient (TS) effects on Compound-C. Preliminary observations of crystal changes were visualized on a hot-stage microscope (HSM). Upon heating Form I crystals of A to about 328–338 K, a few crystals were seen to fly off suddenly from the hot stage to a few centimetres in height (1–2 cm, Fig. 1a) and moved outside the camera zone, while other bits were fragmented into small pieces during heating. Form II crystals of A did not exhibit any thermal response. Crystals of B showed cracking upon heating (Fig. S4a in the supporting information) and Compound-C led to rapid breaking and separation of debris (Fig. 1b) at 363–368 K. Crystals of compounds-D and E were unresponsive to thermal stress.

Figure 1
(a) HSM images of Compound-A Form I crystals during heating. (b) HSM images of Compound-C Form I crystals, and separation of debris during heating.

3.1. X-ray crystal structures

The X-ray crystal structures of Compound-A Form I and III were solved in the monoclinic space group P2₁/c. The hydrazine N—H bonds to the pyridine N-acceptor [N2—H2B⋯N3 = 2.17 (1) Å and 156 (4)° for Form I, and 2.23 (1) Å and 158.7 (1)° for Form III; Fig. 2a] to form a chain along the b axis. Such chains extend through type II halogen bonds [Form I: C—Cl⋯Cl—C, θ₁ = 155.44 (5)°, θ₂ = 95.96 (5)°; Form III: θ₁ = 155.5 (4)°, θ₂ = 95.2 (3)°; Fig. 2b] (Metrangolo & Resnati, 2014 ; Mukherjee & Desiraju, 2014 ). An intramolecular hydrogen bond is present between the imine N atom and the phenolic H atom [O2—H2A⋯N1 = 1.86(2) Å and 145° and 1.88 (1) Å and 144.1 (4)° for Forms I and III, respectively, forming an S(6) ring motif. In the case of Form II, crystals were obtained by fast evaporation of solvent from the solution and the structure was solved and refined in orthorhombic space group Pca2₁ with one molecule in the asymmetric unit. Similar to Form I, Form II also has the same type of one-dimensional chains (Fig. 3a) and the chain grows parallel to the c axis. The one-dimensional chains are extended by type II [C—Cl⋯Cl—C, θ₁ = 151.2 (1)°, θ₂ = 100.21 (8)°] halogen-bonding interactions (Saha et al., 2006 ). Similar to Forms I and III, Form II also reveals the same types of hydrogen- and halogen-bonding interactions except for changes in the halogen/hydrogen-bonding distances (Table 1).

Table 1
Selected halogen- and hydrogen-bond distances in all nine polymorphic structures

Compound	Polymorph	X⋯X (Å)	N—H⋯N (Å)
Compound-A	Forms I, II, III	3.435 (6), 3.395 (1), 3.448 (4)	2. 17 (1), 2.24 (2), 2.23 (1)
Compound-B	Forms I, II	3.587 (1), 3.415 (1)	2.13 (2)
Compound-C	Forms I, II	3.4962 (9), 3.50 (1)	2.16 (3), 2.22 (3)
Compound-D		3.8561 (5)	2.15 (5)
Compound-E			2.19 (1)

Figure 2
(a) The one-dimensional chain of Form I of Compound-A propagating through the N—H⋯N (pyridine) synthon. (b) Type II halogen bonding. (c) Packing of molecules along the a and c axes (Form I).

Figure 3
(a) The one-dimensional chain of Form II of Compound-A propagating through the N—H⋯N (pyridine) synthon. (b) Packing of molecules along the a and b axes (Form II). (c) Packing of molecules along the a and c axes (Form III). (d) Overlay of the Form I (green), Form II (blue) and Form III (red, high-temperature polymorph) crystal structures (Compound-A).

Compound-B Form I crystallized from methanol solvent and was solved in the monoclinic crystal system, space group P2₁/c, with one molecule in the asymmetric unit. Similar to Form I of the dichloro derivative, the hydrazine H atom interacts with the pyridine N atom through an N2—H2B⋯N3 hydrogen bond [2.13 (2) Å and 152.4 (1)°], forming a one-dimensional chain (Fig. 4a). These chains grow parallel to the b axis and are extended by type II halogen bonds [C—Br⋯Br—C, θ₁ = 166.0 (1)°, θ₂ = 94.4 (1)° Fig. 4b]. Form II was obtained by heating Form I crystals. It crystallized in the triclinic space group $[P{\overline 1}]$ with two molecules in the asymmetric unit. A tetrameric ring motif is formed through N2—H2B⋯O3 [2.15 (1) Å and 164.2 (1)°] and N5—H5B⋯O1 [2.11 (1) Å and 168.9 (1)°; Fig. 4c] hydrogen-bonding interactions, forming an R₄⁴(16) motif. The tetrameric rings are extended by type I halogen bonds [C—Br⋯Br—C, θ₁ = θ₂ = 142.6 (2)°]. There are significant differences in the dihedral angles between the two rings before [Form I, ring atom numbers C1–C6 and C9–C13/N3 15.55 (3)°] and after phase transformation [Form II, ring atom numbers C14–C19 and C22–C26/N6 41.36(3)°, and ring atom numbers C1–C6 and C9–C13/N3 4.47 (4)°; Table 2].

Table 2
Dihedral angles between the two rings C1–C6 and C9–C13/N3

Compound	Dihedral angle (°)
Compound-A Forms I, II and III	10.26 (8), 9.76 (1) and 10.95 (6)
Compound-B Form I	15.55 (3)
Compound-B Form II	41.36 (3)† and 4.47 (4)
Compound-C Forms I, II	12.05 (2), 10.54 (3)
Compound-D	19.72 (2)
Compound-E	5.34 (2)

†In Compound-B Form II, the dihedral angle of 41.36° is between the rings C14–C19 and C22–C26/N6.

Figure 4
(a) Type II halogen-bonding interactions of Compound-B. (b) The one-dimensional chain propagating through the N—H⋯N (pyridine) synthon (Form I) and packing of molecules along the c axis. (c) The tetrameric ring motif (Form II) and packing diagram (along the c axis). (d) Overlay of Form I (red) and Form II (green and magenta) of Compound-B.

Similar to the above two compounds, Compound-C (Forms I and II) also has the same types of hydrogen- and halogen-bonding interactions: N2—H2B⋯N3 [2.16 (3) Å and 156 (2)°, and 2.22 (3) Å and 156 (3)°] in a one-dimensional chain (Fig. 5a) and type II [Form I, C—Cl⋯Br—C, θ₁ = 167.48 (8)°, θ₂ = 98.49 (9)°; Form II, C—Cl⋯Br—C, θ₁ = 163.1 (1)°, θ₂ = 97.9 (1)°; Fig. 5b] halogen bonds between the chains.

Figure 5
(a) The one-dimensional chain propagating through the N—H⋯N (amino-pyridine) synthon (Form I, Compound-C). (b) Cl⋯Br type II halogen-bonding interactions. (c) Overlay of Form I (green) and Form II (red) molecules.

In the crystal structure of Compound-D, dimers are formed through C—I⋯O halogen-bonding interactions and these dimers are extended via type II halogen bonds [C—I⋯I—C, 3.856 Å and θ₁ = 170.3 (1)°, θ₂ = 91.95 (9)°; Fig. 6a] and N2—H2B⋯N3 [2.15 (5) Å and 146 (5)°; Fig. 6b) hydrogen-bonding interactions.

Figure 6
(a) Type II (I⋯I) halogen bonding of Compound-D. (b) The dimers extended via N—H⋯N hydrogen bonds (Compound-D).

Similar to the above structures, in Compound-E the same type of N2—H2B⋯N3 hydrogen bonds are present (Fig. S5 in the supporting information) but halogen bonding is absent for the fluoro group, which does not generally engage in intermolecular interactions (Dikundwar et al., 2014 ; Chopra & Row, 2011 ).

3.2. VT-PXRD and thermal analysis

In order to understand the events observed on the hot-stage microscope, both DSC and variable-temperature PXRD were performed on all the materials. Heating Compound-A, Form I showed an endotherm at 330.4 K, indicating the transformation of Form I to Form III (Nauha & Bernstein, 2014 ). Cooling the same material exhibited an exotherm at 308–318 K, indicating Form III → Form I conversion. Reheating the same material showed an endotherm at 328.4 K (Form I → Form III) followed by melting at 523.9 K (Fig. 7a, and Fig. S6a in the supporting information). These observations suggest that Forms I and III are enantiotropic polymorphs and that Form III is stable after the phase transition (high-temperature polymorph, VT-PXRD plots in Fig. 6b). In the case of Form II (Compound-A) an endotherm was observed at 513.3 K after Form II converted into Form III. On cooling the same solid, Form III transformed into Form I and showed an exotherm at 278–293 K. On reheating the same material, an endotherm was observed at 323.8 K followed by melting at 523.3 K (Fig. 8). Apart from heating, competitive slurry experiments (in solution medium, methanol as solvent) suggest that Form II is more stable than Form I. Heating Compound-B showed a small endotherm at 486.1 K and a second endotherm at 492.6 K, which indicates the transformation of Form I into Form II, followed by melting at 519.3 K (Fig. 9). This means that Forms I and II are enantiotropically related.

Figure 7
(a) DSC thermogram of Compound-A Form I crystals (heat–cool–reheat). (b) DSC thermogram of Compound-A Form I ground material (heat–cool–reheat).

Figure 8
DSC thermogram of Compound-A Form II (heat–cool–reheat).

Figure 9
DSC thermogram of Compound-B Form I.

In case of Compound-C, an endotherm was observed at 364.4 K for the conversion of Form I to Form II. Cooling the same material showed an exotherm at 343–353 K for the conversion of Form II to Form I, and on reheating of the material an endotherm was observed at 362.7 K followed by melting at 528.5 K (Fig. 10a, and Fig. S7a in the supporting information). The transformation of Form I and Form II is reversible and Form II is stable at high temperature (above 393 K, Fig. S7b). Compounds-D and E melted at 518 and 560 K, respectively, without any phase transformation, indicating the absence of polymorphism in these two compounds (Figs. S8 and S9). DSC of the ground material (Figs. 7b and 10b) showed the same type of reversible phase transitions, wherein the intensity of the peaks was less than those of the single-crystal material thermal profile, indicating that single crystals can withstand the pressure which is accumulated during heating and the release of strain compared with the powder solids. The crystalline materials undergo phase transitions in a very short time (microseconds) and this sudden change is the probable reason for the thermosalient effect. All the observed changes were verified by HSM, DSC and VT-PXRD (Figs. S4, S6, S7, S8, S9 in the supporting information). All experiments were performed multiple times to confirm reproducibility.

Figure 10
(a) DSC thermogram of Compound-C Form I (heat–cool–reheat). (b) DSC thermogram of Compound-C Form I ground material (heat–cool–reheat).

3.3. Powder X-ray analysis

Powder XRD is a nondestructive technique and most useful for the identification of different powder materials. Signature lines for Compound-A (Form I) were observed at 2θ 9.9, 10.9, 14.0, 14.7; Form II at 10.6, 12.0, 14.1, 16.7 and Form III at 10.3, 13.3, 14.3, 17.6; Compound-B Form I at 9.8, 11.3, 12.6, 15.0; Form II at 8.4, 9.0, 13.1, 18.0; Compound-C Form I at 9.9, 10.7, 13.9, 15.1; Form II at 10.2, 14.1, 17.8, 19.0 (Fig. S10).

3.4. Thermomechanical effect and role of halogen bonding

Different thermal events (jumping/separation of debris, and cracking; Fig. 11a) were observed in halogen derivatives such as Compounds-A, -B, and -C even though they are isomorphous (Table 3) and three-dimensionally isostructural (XPac analysis; Fig. S11; Gelbrich et al., 2012 ) and have the same type of hydrogen/halogen-bonding interactions and similar packing (Fig. 12), except for the change of halogen atom. During heating of Compound-A, jumping/explosion of crystals later converted into fine powder, Compounds-B and C showed breaking and cracking of the crystal into pieces during the phase transition, and no effect was observed in Compounds-D and E. In the present study, all compounds except B (Form II) contain type II halogen-bonding interactions, i.e. those with an attractive δ⁺⋯δ^– polarization (Metrangolo & Resnati, 2014; Mukherjee & Desiraju, 2014). Type II interactions are strong and attractive in nature (Bui et al., 2009 ). Due to the anisotropic distribution of electrons on the heavier halogen atoms, a partial positive charge develops opposite to the sigma bond (σ hole) and a partial negative charge in the equatorial region, leading to an attractive δ⁺⋯δ^– interaction (Fig. 13). The exception is the fluorine atom (Thalladi et al., 1998 ) which is hard, highly electronegative and non-polarizable. On moving from chlorine to iodine, the polar flattening of the halogen atom increases due to the decrease in electronegativity and the increase in polarizability, thereby resulting in a stronger type II inter-halogen bond (Desiraju & Parthasarathy, 1989 ). The electrostatic nature of type II halogen bonding (Metrangolo & Resnati, 2014; Mukherjee & Desiraju, 2014) means that crystal structures containing these interactions are more responsive to temperature changes (thermosalient effects). Saraswatula & Saha (2014 ) reported that thermal expansion of inter-halogen distances is higher for lower halogens (chlorine) and a decrease in expansion was observed with an increase in the halogen-bond strength. So the behaviour of heavier halogen atom-containing species is different from that of the lower halogens. Fluorine is an exception to showing halogen bonding due to its high electronegativity. In effect, the stronger halogen-bonded structures (Table 4) with Br and I atoms make them less responsive to temperature and mechanical stress because the halogen bond is too strong for the heavier halogens to show structural dynamics and mechanical property effects. The decreasing order of thermal response for inter-halogen interactions is Cl⋯Cl > Cl⋯Br > Br⋯Br > I⋯I, indicating the importance of weaker Cl⋯Cl interactions in exhibiting a mechanical response of molecular crystals and temperature effects.

Table 3
Unit-cell similarity index (Π)

Compound	Unit cell similarity index (Π)
Compounds-A and -B	0.0139
Compounds-B and -C	0.0020
Compounds-C and -D	0.0246
Compounds-D and -E	0.0735
Compounds-A and -D	0.0362
Compounds-A and -E	0.0344

Table 4
Strength of halogen bonds†

Compound	Halogen bond (X⋯X)	Stabilization energy (kcal mol⁻¹)
Compound-A (Forms I and II)	Cl⋯Cl	−4.18, −5.31
Compound-B (Form I)	Br⋯Br	−4.39
Compound-C (Form I)	Cl⋯Br	−4.24
Compound-D	I⋯I	−4.70

†See Table S3 in the supporting information for full details.

Figure 11
(a) Thermosalient effects of crystals, such as (i) jumping/explosion, (ii) cracking and (iii) rapid breaking of a crystal into two pieces during the phase transition. (iv) The iodine derivative crystal is intact upon heating. (b) Morphology and faces of Form I crystals of Compounds-A and C.

Figure 12
Packing of molecules in the halogen derivatives A to E to show the similarity.

Figure 13
Halogen-bonding interactions and hydrogen-bonding synthons in the present study.

Heating the crystals of Compound-A Form I in the ( $[0{\overline 1} 1]$ )/( $[0 1{\overline 1}]$ ) (Fig. 11b) faces resulted in a thermal response of the crystals, some of which were seen to fly off the hot stage while a few others exploded into pieces at 330 K. They converted into metastable Form III, with an increase in cell parameters along the a axis (7.7%) and a decrease in the b and c axes (4.5 and 0.8%, respectively) and an increase in volume (of 2.1%, Table 5). During cooling the crystals moved without any disintegration. Heat–cool cycles were conducted 3–4 times, after which the crystals exhibiting a thermal response turned to powder. Similarly, Form II also converted into Form III at 513 K without any thermal response. Comparison of the two crystal structures (Forms I and II) showed changes in the hydrogen-bond distances and packing of the molecules. In a Hirshfeld analysis (Fig. 14, and Fig. S12), Form II has a greater contribution from Cl⋯H, O⋯H, N⋯H and Cl⋯Cl contacts (47.3%) compared with Form I (45.7%), and the halogen-bond distances are shorter (stronger bonding) in Form II compared with Form I (Tables 1, 4), thus supporting the non-thermosalient transformation of Form II to Form III.

Table 5
Cell parameters and phase transitions of the polymorphs

Transition	T (K) DSC	Form	a axis (Å)	b axis (Å)	c axis (Å)	Volume (Å³)
Compound-A	298–326	I†	8.0683 (4)	10.7464 (6)	15.6155 (8)	1353.78 (12)
I→III	330–332	III‡	8.6916 (6)	10.2641 (7)	15.4965 (10)	1382.46 (16)
		Difference (%)	7.72	−4.48	−0.76	2.11
Compound-B		I†	8.266 (2)	10.917 (2)	15.734 (3)	1412.7 (5)
I→II		II†	9.8084 (7)	10.7751 (8)	13.9516 (9)	1429.11 (17)
		Difference (%)	18.65	−1.29	−11.33	1.16
Compound-C	298–358	I†	8.2475 (9)	10.8035 (11)	15.7971 (15)	1399.6 (2)
I→II	360–366	II§	8.651 (2)	10.446 (3)	15.680 (4)	1413.3 (7)
		Difference (%)	4.89	−3.30	−0.74	0.97

†Unit cell measured at 298 K.
‡Unit cell measured at 338 K.
§Unit cell measured at 368 K.

Figure 14
Hirshfeld surface analysis for polymorphs of Compounds-A, -B and -C, showing the contributions of the different hydrogen- and halogen-bonding interactions.

On heating crystals of Compound-B Form I on the ( $[0{\overline 1} {\overline 1}]$ )/(011) faces (Fig. S13), Form I transformed to Form II with cracking, with an increase in Z′ from 1 to 2 and a lengthening of the a axis (18.7%) and a decrease in the b and c axes (1.3 and 11.3%, respectively), but with a negligible increase in the overall cell volume (1.2%).

Rapid breaking of the crystals was observed during heating of Compound-C Form I crystals on the ( $[0{\overline 1} 1]$ )/( $[0 1{\overline 1}]$ ) faces (Fig. 11b), with an expansion on the a axis and contraction along the b and c axes.

To understand the thermal response of these molecular crystals, the room-temperature and high-temperature polymorphic structures of Compounds-A, -B and -C were compared. The integrity of the hydrogen-bonding interactions is retained in the structures of Compounds-A (Form I → Form III) and C (Form I → Form II) without any significant changes in dihedral angles (Table 2), hydrogen- and halogen-bond distances or packing of the molecules, before and after the phase transition (Table 1). However, in the case of Compound-A Form II → Form III and Compound-B Form I → Form II, the transition occurs with significant changes in hydrogen- and halogen-bonding interactions and in the packing of the molecules. A probable reason for the thermal response is ascribed to the rapid release of accumulated strain during the phase transition and anisotropy in the structural parameters.

3.5. Photochromism

Photochromism (Safin et al., 2014; Cohen et al., 1964 ; Senier & Shepheard, 1909 ; Zbačnik & Kaitner, 2014 ) of both organic and inorganic materials is defined as the reversible colour change of a material on exposure to electromagnetic radiation such as UV, visible light or IR. The sensitivity of such materials towards light makes them potential candidates in reusable information storage media, data displays, chemical switches for computers etc. (Gust et al., 2012 ; Kawata & Kawata, 2000 ). The salinazid derivatives presented in this study show thermochromic and photochromic behaviour in the solid state.

The accepted mechanism for photochromism is the transfer of a proton to the N atom (cis-keto) followed by isomerization of cis-keto to trans-keto isomers (Scheme 4) (Hadjoudis & Mavridis, 2004 ). The dihedral angle between two phenyl rings is the predictor for photochromism. If the angle is >30° then the compounds are photochromic, if the angle is 20–30° the compounds are either photochromic or non-photochromic, and if the angle is <20° then the compounds are non-photochromic (Carletta et al., 2016 ). The polymorphs of Compound-B show photochromism in the solid state during exposure to UV light (365 nm). The dihedral angles in Form I and Form II are 15° and 42°, respectively, and the former crystal is cyan in colour and the latter is light orange (Fig. 15).

Figure 15
(Left) Compound-B Form I and Form II (a) under normal light and (b) under UV at 365 nm. (Right) The variation in the conformation of the molecule.

4. Conclusions

In the present investigation we have explored the mechanical response of organic crystals towards thermal stress and the role of type II halogen bonding in tuning the properties of materials. The dichloro (Form I) derivative of the Schiff base shows excellent thermal effects, and a decrease in thermal effects was observed with the more polarizable (and less electronegative) iodine in the order Cl⋯Cl > Br⋯Cl > Br⋯Br > I⋯I. These effects are ascribed to anisotropy in the cell parameters and to the sudden release of accumulated strain during the phase transition. Our results demonstrate the importance of weak halogen-bonding interactions (Cl⋯Cl) of the type II variety in a family of thermally stable and highly reversible self-actuating materials.

Supporting information

CCDC references: 1579384; 1548278; 1548279; 1548280; 1548281; 1548282; 1548283; 1548284; 1548285

Crystal structure: contains datablocks Compound-A-Form-I, Compound-A-Form-II, Compound-A-Form-III, Compound-B-Form-I, Compound-B-Form-II, Compound-C-Form-I, Compound-C-Form-II, Compound-D, Compound-E. DOI: https://doi.org/10.1107/S2052252517014658/ed5012sup1.cif

Structure factors: contains datablock Compound-A-Form-I. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-A-Form-Isup2.hkl

Structure factors: contains datablock Compound-A-Form-II. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-A-Form-IIsup3.hkl

Structure factors: contains datablock Compound-A-Form-III. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-A-Form-IIIsup4.hkl

Structure factors: contains datablock Compound-B-Form-I. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-B-Form-Isup5.hkl

Structure factors: contains datablock Compound-B-Form-II. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-B-Form-IIsup6.hkl

Structure factors: contains datablock Compound-C-Form-I. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-C-Form-Isup7.hkl

Structure factors: contains datablock Compound-C-Form-II. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-C-Form-IIsup8.hkl

Structure factors: contains datablock Compound-D. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-Dsup9.hkl

Structure factors: contains datablock Compound-E. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-Esup10.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-Asup11.cml

Supporting information file. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-Bsup12.cml

Supporting information file. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-Csup13.cml

Supporting information file. DOI: https://doi.org/10.1107/S2052252517014658/ed5012Compound-Dsup14.cml

Additional tables and figures. DOI: https://doi.org/10.1107/S2052252517014658/ed5012sup15.pdf

Computing details top

For all structures, program(s) used to refine structure: SHELXL2014/7 (Sheldrick, 2014).

(E)-N'-(3,5-dichloro-2-hydroxybenzylidene)isonicotinohydrazide (Compound-A-Form-I) top

Crystal data top

C₁₃H₉Cl₂N₃O₂	D_x = 1.522 Mg m⁻³
M_r = 310.13	Melting point: 523.7K K
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.0683 (4) Å	Cell parameters from 2690 reflections
b = 10.7464 (6) Å	θ = 2.3–27.6°
c = 15.6155 (8) Å	µ = 0.48 mm⁻¹
β = 90.890 (2)°	T = 298 K
V = 1353.78 (12) Å³	Block, colorless
Z = 4	0.32 × 0.31 × 0.28 mm
F(000) = 632

Data collection top

Bruker APEX-II CCD diffractometer	R_int = 0.035
φ and ω scans	θ_max = 27.6°, θ_min = 2.3°
35148 measured reflections	h = −10→10
3124 independent reflections	k = −13→13
2690 reflections with I > 2σ(I)	l = −20→20

Refinement top

Refinement on F²	Hydrogen site location: mixed
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.033	w = 1/[σ²(F_o²) + (0.0456P)² + 0.3954P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.092	(Δ/σ)_max < 0.001
S = 1.03	Δρ_max = 0.30 e Å⁻³
3124 reflections	Δρ_min = −0.31 e Å⁻³
183 parameters	Extinction correction: SHELXL-2014/7 (Sheldrick 2014, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.080 (5)

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	0.68668 (5)	0.95451 (4)	0.55026 (3)	0.05284 (15)
Cl2	0.44976 (7)	0.63879 (5)	0.78546 (2)	0.06728 (18)
O1	0.05349 (15)	0.28912 (10)	0.51348 (6)	0.0515 (3)
O2	0.30262 (16)	0.51237 (10)	0.64130 (7)	0.0514 (3)
H2A	0.2603	0.4795	0.5989	0.077*
N3	−0.12454 (18)	0.07913 (13)	0.24296 (8)	0.0499 (3)
N2	0.14982 (15)	0.42588 (11)	0.41643 (7)	0.0391 (3)
H2B	0.1529	0.4504	0.3640	0.047*
N1	0.22813 (15)	0.49028 (11)	0.48088 (7)	0.0382 (3)
C6	0.39811 (16)	0.65331 (12)	0.53155 (8)	0.0342 (3)
C9	−0.00283 (16)	0.24314 (12)	0.36750 (8)	0.0351 (3)
C1	0.49152 (17)	0.75802 (12)	0.51227 (8)	0.0371 (3)
H1	0.5019	0.7828	0.4555	0.044*
C5	0.38629 (17)	0.61430 (12)	0.61749 (8)	0.0370 (3)
C8	0.06692 (17)	0.32132 (12)	0.43935 (8)	0.0372 (3)
C7	0.31405 (17)	0.58552 (13)	0.46282 (8)	0.0379 (3)
H7	0.3232	0.6117	0.4063	0.045*
C2	0.56868 (17)	0.82520 (12)	0.57621 (9)	0.0379 (3)
C3	0.55524 (18)	0.79128 (13)	0.66107 (9)	0.0415 (3)
H3	0.6049	0.8385	0.7043	0.050*
C4	0.46634 (19)	0.68566 (13)	0.68006 (8)	0.0406 (3)
C10	0.0273 (2)	0.26237 (14)	0.28181 (9)	0.0476 (4)
H10	0.0887	0.3308	0.2642	0.057*
C13	−0.09637 (19)	0.14102 (14)	0.38930 (10)	0.0449 (3)
H13	−0.1198	0.1250	0.4464	0.054*
C11	−0.0351 (2)	0.17828 (16)	0.22252 (10)	0.0536 (4)
H11	−0.0131	0.1919	0.1650	0.064*
C12	−0.1548 (2)	0.06305 (15)	0.32589 (11)	0.0513 (4)
H12	−0.2191	−0.0047	0.3418	0.062*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0520 (2)	0.0411 (2)	0.0653 (3)	−0.00523 (15)	−0.00396 (18)	0.00434 (16)
Cl2	0.1070 (4)	0.0663 (3)	0.0283 (2)	−0.0009 (2)	−0.0076 (2)	0.00565 (16)
O1	0.0754 (8)	0.0497 (6)	0.0296 (5)	−0.0033 (5)	0.0049 (5)	−0.0047 (4)
O2	0.0739 (8)	0.0438 (6)	0.0364 (5)	−0.0106 (5)	0.0004 (5)	0.0046 (4)
N3	0.0602 (8)	0.0459 (7)	0.0435 (7)	−0.0036 (6)	−0.0070 (6)	−0.0090 (6)
N2	0.0533 (7)	0.0345 (6)	0.0294 (5)	0.0022 (5)	−0.0051 (5)	−0.0047 (4)
N1	0.0467 (6)	0.0337 (6)	0.0340 (6)	0.0068 (5)	−0.0046 (5)	−0.0070 (4)
C6	0.0402 (7)	0.0324 (6)	0.0298 (6)	0.0085 (5)	−0.0029 (5)	−0.0009 (5)
C9	0.0392 (7)	0.0337 (6)	0.0323 (6)	0.0063 (5)	0.0001 (5)	−0.0037 (5)
C1	0.0441 (7)	0.0357 (7)	0.0313 (6)	0.0071 (5)	−0.0011 (5)	0.0041 (5)
C5	0.0458 (7)	0.0332 (6)	0.0319 (6)	0.0060 (5)	−0.0009 (5)	0.0014 (5)
C8	0.0446 (7)	0.0351 (7)	0.0318 (6)	0.0076 (5)	0.0018 (5)	−0.0059 (5)
C7	0.0478 (8)	0.0355 (7)	0.0302 (6)	0.0081 (6)	−0.0033 (5)	−0.0018 (5)
C2	0.0387 (7)	0.0320 (6)	0.0427 (7)	0.0054 (5)	−0.0045 (6)	0.0017 (5)
C3	0.0461 (7)	0.0392 (7)	0.0389 (7)	0.0076 (6)	−0.0116 (6)	−0.0051 (6)
C4	0.0536 (8)	0.0415 (7)	0.0266 (6)	0.0092 (6)	−0.0040 (6)	0.0018 (5)
C10	0.0682 (10)	0.0398 (8)	0.0349 (7)	−0.0091 (7)	−0.0011 (7)	0.0001 (6)
C13	0.0506 (8)	0.0467 (8)	0.0377 (7)	−0.0043 (6)	0.0070 (6)	−0.0034 (6)
C11	0.0797 (12)	0.0501 (9)	0.0309 (7)	−0.0052 (8)	−0.0028 (7)	−0.0032 (6)
C12	0.0569 (9)	0.0480 (9)	0.0491 (9)	−0.0123 (7)	0.0026 (7)	−0.0055 (7)

Geometric parameters (Å, º) top

Cl1—C2	1.7360 (15)	C9—C10	1.379 (2)
Cl2—C4	1.7285 (14)	C9—C8	1.5039 (18)
O1—C8	1.2147 (17)	C1—C2	1.3735 (19)
O2—C5	1.3422 (17)	C1—H1	0.9300
O2—H2A	0.8200	C5—C4	1.393 (2)
N3—C11	1.329 (2)	C7—H7	0.9300
N3—C12	1.333 (2)	C2—C3	1.380 (2)
N2—C8	1.3585 (19)	C3—C4	1.377 (2)
N2—N1	1.3679 (16)	C3—H3	0.9300
N2—H2B	0.8600	C10—C11	1.383 (2)
N1—C7	1.2703 (19)	C10—H10	0.9300
C6—C1	1.3899 (19)	C13—C12	1.375 (2)
C6—C5	1.4107 (18)	C13—H13	0.9300
C6—C7	1.4559 (18)	C11—H11	0.9300
C9—C13	1.378 (2)	C12—H12	0.9300

C5—O2—H2A	109.5	C6—C7—H7	120.4
C11—N3—C12	116.48 (13)	C1—C2—C3	121.17 (13)
C8—N2—N1	116.64 (11)	C1—C2—Cl1	119.68 (11)
C8—N2—H2B	121.7	C3—C2—Cl1	119.14 (11)
N1—N2—H2B	121.7	C4—C3—C2	118.25 (13)
C7—N1—N2	119.46 (12)	C4—C3—H3	120.9
C1—C6—C5	119.44 (12)	C2—C3—H3	120.9
C1—C6—C7	119.56 (12)	C3—C4—C5	122.68 (12)
C5—C6—C7	120.99 (13)	C3—C4—Cl2	119.57 (11)
C13—C9—C10	117.69 (13)	C5—C4—Cl2	117.75 (11)
C13—C9—C8	117.44 (12)	C9—C10—C11	118.92 (14)
C10—C9—C8	124.78 (13)	C9—C10—H10	120.5
C2—C1—C6	120.62 (12)	C11—C10—H10	120.5
C2—C1—H1	119.7	C12—C13—C9	119.38 (14)
C6—C1—H1	119.7	C12—C13—H13	120.3
O2—C5—C4	119.00 (12)	C9—C13—H13	120.3
O2—C5—C6	123.21 (12)	N3—C11—C10	123.82 (14)
C4—C5—C6	117.79 (13)	N3—C11—H11	118.1
O1—C8—N2	122.56 (13)	C10—C11—H11	118.1
O1—C8—C9	120.93 (13)	N3—C12—C13	123.70 (15)
N2—C8—C9	116.47 (12)	N3—C12—H12	118.2
N1—C7—C6	119.28 (12)	C13—C12—H12	118.2
N1—C7—H7	120.4

C8—N2—N1—C7	176.73 (12)	C6—C1—C2—Cl1	179.22 (10)
C5—C6—C1—C2	−1.6 (2)	C1—C2—C3—C4	2.0 (2)
C7—C6—C1—C2	178.43 (12)	Cl1—C2—C3—C4	−177.54 (10)
C1—C6—C5—O2	−178.07 (13)	C2—C3—C4—C5	−1.8 (2)
C7—C6—C5—O2	1.9 (2)	C2—C3—C4—Cl2	178.91 (11)
C1—C6—C5—C4	1.73 (19)	O2—C5—C4—C3	179.78 (13)
C7—C6—C5—C4	−178.29 (12)	C6—C5—C4—C3	0.0 (2)
N1—N2—C8—O1	4.2 (2)	O2—C5—C4—Cl2	−0.93 (19)
N1—N2—C8—C9	−173.41 (11)	C6—C5—C4—Cl2	179.26 (10)
C13—C9—C8—O1	6.4 (2)	C13—C9—C10—C11	−0.9 (2)
C10—C9—C8—O1	−169.94 (15)	C8—C9—C10—C11	175.47 (15)
C13—C9—C8—N2	−175.95 (12)	C10—C9—C13—C12	0.2 (2)
C10—C9—C8—N2	7.7 (2)	C8—C9—C13—C12	−176.39 (14)
N2—N1—C7—C6	−179.58 (11)	C12—N3—C11—C10	0.6 (3)
C1—C6—C7—N1	−179.62 (12)	C9—C10—C11—N3	0.5 (3)
C5—C6—C7—N1	0.4 (2)	C11—N3—C12—C13	−1.3 (3)
C6—C1—C2—C3	−0.3 (2)	C9—C13—C12—N3	0.9 (3)

(E)-N'-(3,5-dichloro-2-hydroxybenzylidene)isonicotinohydrazide (Compound-A-Form-II) top

Crystal data top

C₁₃H₉Cl₂N₃O₂	D_x = 1.513 Mg m⁻³
M_r = 310.13	Melting point: 523.1K K
Orthorhombic, Pca2₁	Mo Kα radiation, λ = 0.71073 Å
a = 15.441 (3) Å	Cell parameters from 2279 reflections
b = 8.3179 (16) Å	θ = 2.5–25.0°
c = 10.6014 (18) Å	µ = 0.48 mm⁻¹
V = 1361.6 (5) Å³	T = 298 K
Z = 4	Block, colorless
F(000) = 632	0.32 × 0.31 × 0.29 mm

Data collection top

Bruker APEX-II CCD diffractometer	R_int = 0.024
φ and ω scans	θ_max = 25.0°, θ_min = 2.5°
8992 measured reflections	h = −18→18
2379 independent reflections	k = −9→9
2279 reflections with I > 2σ(I)	l = −12→12

Refinement top

Refinement on F²	Hydrogen site location: mixed
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.025	w = 1/[σ²(F_o²) + (0.036P)² + 0.1165P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.063	(Δ/σ)_max < 0.001
S = 1.10	Δρ_max = 0.12 e Å⁻³
2379 reflections	Δρ_min = −0.17 e Å⁻³
182 parameters	Absolute structure: Flack x determined using 1021 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons, Flack and Wagner, Acta Cryst. B69 (2013) 249-259).
1 restraint	Absolute structure parameter: 0.021 (19)

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	0.29365 (5)	0.33456 (8)	0.94717 (7)	0.04828 (19)
Cl2	0.54518 (4)	0.58962 (13)	0.65670 (10)	0.0727 (3)
O2	0.40394 (11)	0.7279 (3)	0.51691 (19)	0.0471 (5)
H2A	0.3613	0.7679	0.4790	0.071*
O1	0.27275 (12)	0.9819 (3)	0.28572 (18)	0.0461 (5)
N1	0.24057 (14)	0.8019 (2)	0.48623 (19)	0.0338 (5)
N2	0.17509 (13)	0.8769 (3)	0.42154 (18)	0.0345 (5)
H2B	0.1208	0.8694	0.4462	0.041*
N3	−0.00546 (15)	1.1355 (3)	0.0746 (2)	0.0470 (6)
C7	0.22031 (15)	0.7137 (3)	0.5797 (2)	0.0338 (5)
H7	0.1613	0.7021	0.6033	0.041*
C8	0.19745 (15)	0.9632 (3)	0.3179 (2)	0.0315 (5)
C1	0.26358 (16)	0.5362 (3)	0.7532 (2)	0.0333 (5)
H1	0.2042	0.5264	0.7756	0.040*
C9	0.12365 (16)	1.0281 (3)	0.2397 (2)	0.0317 (5)
C2	0.32615 (16)	0.4564 (3)	0.8225 (2)	0.0337 (5)
C6	0.28748 (14)	0.6306 (3)	0.6507 (2)	0.0307 (5)
C13	0.14417 (17)	1.1085 (3)	0.1303 (3)	0.0406 (6)
H13	0.2030	1.1283	0.1088	0.049*
C5	0.37595 (16)	0.6439 (3)	0.6174 (2)	0.0340 (5)
C3	0.41280 (18)	0.4721 (3)	0.7952 (3)	0.0408 (6)
H3	0.4554	0.4195	0.8450	0.049*
C12	0.07833 (19)	1.1601 (4)	0.0520 (3)	0.0460 (7)
H12	0.0938	1.2166	−0.0226	0.055*
C4	0.43638 (16)	0.5665 (3)	0.6931 (3)	0.0400 (6)
C10	0.03702 (17)	1.0045 (4)	0.2656 (3)	0.0542 (8)
H10	0.0197	0.9508	0.3405	0.065*
C11	−0.02445 (18)	1.0599 (5)	0.1810 (3)	0.0591 (9)
H11	−0.0838	1.0426	0.2004	0.071*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0590 (4)	0.0458 (3)	0.0400 (3)	−0.0075 (3)	0.0018 (3)	0.0056 (3)
Cl2	0.0263 (3)	0.0979 (7)	0.0938 (7)	0.0144 (4)	0.0107 (4)	0.0318 (5)
O2	0.0344 (10)	0.0617 (13)	0.0451 (10)	0.0066 (9)	0.0076 (9)	0.0143 (9)
O1	0.0258 (10)	0.0639 (12)	0.0486 (12)	0.0031 (8)	0.0021 (7)	0.0031 (9)
N1	0.0294 (11)	0.0388 (10)	0.0331 (11)	0.0063 (9)	−0.0057 (8)	−0.0050 (9)
N2	0.0244 (10)	0.0462 (12)	0.0329 (13)	0.0070 (9)	−0.0025 (8)	0.0000 (9)
N3	0.0353 (13)	0.0663 (16)	0.0395 (13)	0.0042 (11)	−0.0053 (10)	0.0077 (12)
C7	0.0260 (13)	0.0419 (14)	0.0336 (13)	0.0010 (9)	−0.0035 (10)	−0.0059 (11)
C8	0.0253 (13)	0.0361 (13)	0.0332 (13)	0.0026 (9)	−0.0004 (10)	−0.0062 (10)
C1	0.0293 (13)	0.0376 (12)	0.0331 (12)	−0.0042 (10)	0.0010 (10)	−0.0078 (10)
C9	0.0268 (12)	0.0381 (12)	0.0302 (12)	0.0029 (10)	0.0018 (9)	−0.0038 (10)
C2	0.0403 (14)	0.0315 (13)	0.0292 (13)	−0.0023 (10)	−0.0011 (10)	−0.0024 (10)
C6	0.0262 (11)	0.0340 (12)	0.0320 (12)	−0.0007 (9)	−0.0036 (10)	−0.0071 (10)
C13	0.0293 (12)	0.0508 (16)	0.0417 (14)	−0.0059 (11)	0.0015 (11)	0.0065 (12)
C5	0.0287 (12)	0.0379 (13)	0.0354 (12)	0.0021 (10)	0.0057 (10)	−0.0023 (10)
C3	0.0365 (14)	0.0426 (14)	0.0434 (15)	0.0097 (11)	−0.0058 (11)	0.0040 (12)
C12	0.0422 (16)	0.0585 (18)	0.0372 (15)	−0.0025 (13)	−0.0008 (12)	0.0120 (13)
C4	0.0257 (12)	0.0452 (15)	0.0490 (16)	0.0071 (11)	0.0040 (11)	0.0020 (12)
C10	0.0295 (14)	0.090 (2)	0.0432 (16)	0.0062 (15)	0.0056 (12)	0.0251 (16)
C11	0.0248 (13)	0.101 (3)	0.0516 (18)	0.0054 (15)	0.0034 (13)	0.0206 (17)

Geometric parameters (Å, º) top

Cl1—C2	1.739 (3)	C1—C6	1.391 (4)
Cl2—C4	1.734 (3)	C1—H1	0.9500
O2—C5	1.345 (3)	C9—C13	1.376 (4)
O2—H2A	0.8400	C9—C10	1.380 (4)
O1—C8	1.222 (3)	C2—C3	1.375 (4)
N1—C7	1.272 (3)	C6—C5	1.415 (3)
N1—N2	1.372 (3)	C13—C12	1.381 (4)
N2—C8	1.357 (3)	C13—H13	0.9500
N2—H2B	0.8800	C5—C4	1.389 (4)
N3—C11	1.324 (4)	C3—C4	1.386 (4)
N3—C12	1.332 (4)	C3—H3	0.9500
C7—C6	1.456 (3)	C12—H12	0.9500
C7—H7	0.9500	C10—C11	1.385 (4)
C8—C9	1.509 (3)	C10—H10	0.9500
C1—C2	1.384 (4)	C11—H11	0.9500

C5—O2—H2A	109.5	C5—C6—C7	121.5 (2)
C7—N1—N2	118.1 (2)	C9—C13—C12	119.2 (2)
C8—N2—N1	117.2 (2)	C9—C13—H13	120.4
C8—N2—H2B	121.4	C12—C13—H13	120.4
N1—N2—H2B	121.4	O2—C5—C4	118.8 (2)
C11—N3—C12	116.2 (2)	O2—C5—C6	123.2 (2)
N1—C7—C6	120.1 (2)	C4—C5—C6	117.9 (2)
N1—C7—H7	120.0	C2—C3—C4	118.3 (2)
C6—C7—H7	120.0	C2—C3—H3	120.9
O1—C8—N2	122.4 (2)	C4—C3—H3	120.9
O1—C8—C9	121.3 (2)	N3—C12—C13	124.0 (3)
N2—C8—C9	116.2 (2)	N3—C12—H12	118.0
C2—C1—C6	120.1 (2)	C13—C12—H12	118.0
C2—C1—H1	120.0	C3—C4—C5	122.5 (2)
C6—C1—H1	120.0	C3—C4—Cl2	119.4 (2)
C13—C9—C10	117.4 (2)	C5—C4—Cl2	118.1 (2)
C13—C9—C8	117.6 (2)	C9—C10—C11	119.3 (3)
C10—C9—C8	124.9 (2)	C9—C10—H10	120.4
C3—C2—C1	121.5 (2)	C11—C10—H10	120.4
C3—C2—Cl1	119.75 (19)	N3—C11—C10	123.9 (3)
C1—C2—Cl1	118.8 (2)	N3—C11—H11	118.0
C1—C6—C5	119.7 (2)	C10—C11—H11	118.0
C1—C6—C7	118.9 (2)

(E)-N'-(3,5-dichloro-2-hydroxybenzylidene)isonicotinohydrazide (Compound-A-Form-III) top

Crystal data top

C₁₃H₉Cl₂N₃O₂	D_x = 1.490 Mg m⁻³
M_r = 310.13	Melting point: 523.7K K
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.6916 (6) Å	Cell parameters from 1677 reflections
b = 10.2641 (7) Å	θ = 2.3–25.1°
c = 15.4965 (10) Å	µ = 0.47 mm⁻¹
β = 90.186 (2)°	T = 338 K
V = 1382.46 (16) Å³	Block, colorless
Z = 4	0.29 × 0.29 × 0.28 mm
F(000) = 632

Data collection top

Bruker APEX-II CCD diffractometer	R_int = 0.028
φ and ω scans	θ_max = 25.1°, θ_min = 2.3°
12375 measured reflections	h = −10→9
2046 independent reflections	k = −12→12
1677 reflections with I > 2σ(I)	l = −18→18

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.081	H-atom parameters constrained
wR(F²) = 0.294	w = 1/[σ²(F_o²) + 9.3654P] where P = (F_o² + 2F_c²)/3
S = 1.54	(Δ/σ)_max < 0.001
2046 reflections	Δρ_max = 0.29 e Å⁻³
182 parameters	Δρ_min = −0.28 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	0.3353 (3)	0.9181 (3)	0.46016 (19)	0.0736 (9)
Cl2	0.5750 (5)	0.6172 (3)	0.21165 (17)	0.0936 (12)
O1	0.9908 (9)	0.2581 (7)	0.4787 (4)	0.068 (2)
N2	0.8775 (9)	0.3889 (7)	0.5766 (5)	0.052 (2)
H2B	0.8684	0.4115	0.6297	0.062*
N1	0.8025 (9)	0.4557 (8)	0.5123 (5)	0.0505 (19)
O2	0.7283 (10)	0.4856 (7)	0.3515 (4)	0.072 (2)
H2A	0.7814	0.4581	0.3913	0.108*
N3	1.1420 (10)	0.0418 (8)	0.7552 (5)	0.062 (2)
C12	1.1609 (15)	0.0176 (12)	0.6721 (7)	0.083 (4)
H12	1.2139	−0.0575	0.6568	0.100*
C13	1.1074 (13)	0.0961 (11)	0.6071 (6)	0.072 (3)
H13	1.1242	0.0734	0.5498	0.086*
C9	1.0301 (10)	0.2067 (8)	0.6266 (5)	0.045 (2)
C8	0.9667 (10)	0.2861 (9)	0.5536 (6)	0.048 (2)
C7	0.7136 (10)	0.5493 (10)	0.5330 (6)	0.049 (2)
H7	0.7021	0.5719	0.5907	0.059*
C6	0.6304 (9)	0.6208 (8)	0.4669 (5)	0.042 (2)
C1	0.5366 (10)	0.7238 (9)	0.4902 (6)	0.051 (2)
H1	0.5288	0.7469	0.5481	0.061*
C2	0.4550 (10)	0.7926 (9)	0.4294 (6)	0.050 (2)
C3	0.4661 (11)	0.7604 (10)	0.3429 (6)	0.056 (2)
H3	0.4117	0.8071	0.3014	0.067*
C11	1.0681 (14)	0.1493 (11)	0.7733 (6)	0.072 (3)
H11	1.0529	0.1697	0.8311	0.086*
C10	1.0113 (14)	0.2342 (11)	0.7121 (6)	0.074 (3)
H10	0.9606	0.3097	0.7290	0.089*
C5	0.6419 (10)	0.5855 (9)	0.3794 (6)	0.047 (2)
C4	0.5588 (12)	0.6584 (10)	0.3196 (6)	0.055 (2)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0652 (18)	0.0705 (18)	0.085 (2)	0.0115 (15)	0.0052 (14)	−0.0063 (15)
Cl2	0.151 (3)	0.090 (2)	0.0396 (15)	0.019 (2)	−0.0136 (16)	−0.0063 (14)
O1	0.092 (5)	0.073 (5)	0.038 (4)	0.004 (4)	0.004 (3)	0.006 (3)
N2	0.060 (5)	0.055 (5)	0.040 (4)	−0.004 (4)	−0.008 (3)	0.007 (3)
N1	0.051 (5)	0.053 (5)	0.047 (4)	−0.005 (4)	−0.009 (3)	0.010 (4)
O2	0.097 (6)	0.069 (5)	0.051 (4)	0.023 (4)	−0.004 (4)	−0.006 (4)
N3	0.079 (6)	0.060 (5)	0.047 (5)	0.013 (5)	0.001 (4)	0.005 (4)
C12	0.116 (10)	0.079 (8)	0.054 (7)	0.044 (8)	0.009 (6)	0.002 (6)
C13	0.094 (8)	0.083 (8)	0.039 (5)	0.029 (7)	0.008 (5)	0.002 (5)
C9	0.050 (6)	0.045 (5)	0.040 (5)	−0.007 (4)	0.003 (4)	0.004 (4)
C8	0.050 (6)	0.051 (5)	0.043 (5)	−0.009 (5)	0.000 (4)	0.005 (4)
C7	0.045 (5)	0.058 (6)	0.045 (5)	−0.011 (5)	−0.005 (4)	0.004 (4)
C6	0.035 (5)	0.047 (5)	0.044 (5)	−0.010 (4)	−0.005 (4)	0.003 (4)
C1	0.054 (6)	0.054 (6)	0.043 (5)	−0.007 (5)	0.000 (4)	−0.003 (4)
C2	0.042 (5)	0.050 (5)	0.058 (6)	−0.007 (4)	0.001 (4)	−0.002 (4)
C3	0.059 (6)	0.056 (6)	0.052 (6)	−0.005 (5)	−0.011 (5)	0.007 (5)
C11	0.110 (9)	0.069 (7)	0.035 (5)	0.016 (7)	0.000 (5)	0.001 (5)
C10	0.123 (10)	0.058 (6)	0.043 (6)	0.030 (7)	−0.003 (6)	−0.001 (5)
C5	0.047 (5)	0.048 (5)	0.047 (5)	−0.002 (4)	−0.004 (4)	−0.002 (4)
C4	0.070 (7)	0.056 (6)	0.039 (5)	−0.001 (5)	−0.009 (4)	−0.004 (4)

Geometric parameters (Å, º) top

Cl1—C2	1.724 (10)	C9—C10	1.366 (12)
Cl2—C4	1.732 (9)	C9—C8	1.498 (12)
O1—C8	1.214 (10)	C7—C6	1.452 (12)
N2—C8	1.357 (12)	C7—H7	0.9300
N2—N1	1.372 (9)	C6—C1	1.384 (12)
N2—H2B	0.8600	C6—C5	1.406 (12)
N1—C7	1.275 (12)	C1—C2	1.373 (13)
O2—C5	1.343 (11)	C1—H1	0.9300
O2—H2A	0.8200	C2—C3	1.384 (13)
N3—C11	1.308 (13)	C3—C4	1.370 (13)
N3—C12	1.321 (13)	C3—H3	0.9300
C12—C13	1.370 (14)	C11—C10	1.377 (13)
C12—H12	0.9300	C11—H11	0.9300
C13—C9	1.353 (13)	C10—H10	0.9300
C13—H13	0.9300	C5—C4	1.391 (12)

C8—N2—N1	117.9 (8)	C5—C6—C7	120.9 (8)
C8—N2—H2B	121.0	C2—C1—C6	121.1 (8)
N1—N2—H2B	121.0	C2—C1—H1	119.5
C7—N1—N2	118.7 (8)	C6—C1—H1	119.5
C5—O2—H2A	109.5	C1—C2—C3	120.3 (9)
C11—N3—C12	115.4 (9)	C1—C2—Cl1	120.3 (7)
N3—C12—C13	124.3 (10)	C3—C2—Cl1	119.4 (8)
N3—C12—H12	117.9	C4—C3—C2	118.7 (9)
C13—C12—H12	117.9	C4—C3—H3	120.6
C9—C13—C12	119.8 (9)	C2—C3—H3	120.6
C9—C13—H13	120.1	N3—C11—C10	124.2 (9)
C12—C13—H13	120.1	N3—C11—H11	117.9
C13—C9—C10	116.7 (9)	C10—C11—H11	117.9
C13—C9—C8	118.1 (8)	C9—C10—C11	119.6 (10)
C10—C9—C8	125.1 (9)	C9—C10—H10	120.2
O1—C8—N2	122.4 (9)	C11—C10—H10	120.2
O1—C8—C9	121.9 (9)	O2—C5—C4	119.0 (8)
N2—C8—C9	115.7 (8)	O2—C5—C6	123.3 (8)
N1—C7—C6	120.3 (8)	C4—C5—C6	117.7 (8)
N1—C7—H7	119.9	C3—C4—C5	122.7 (8)
C6—C7—H7	119.9	C3—C4—Cl2	119.4 (7)
C1—C6—C5	119.5 (8)	C5—C4—Cl2	117.9 (8)
C1—C6—C7	119.6 (8)

(E)-N'-(3,5-dibromo-2-hydroxybenzylidene)isonicotinohydrazide (Compound-B-Form-I) top

Crystal data top

C₁₃H₉Br₂N₃O₂	D_x = 1.876 Mg m⁻³
M_r = 399.05	Melting point: 519K K
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71075 Å
a = 8.266 (2) Å	Cell parameters from 2697 reflections
b = 10.917 (2) Å	θ = 3.1–28.1°
c = 15.734 (3) Å	µ = 5.74 mm⁻¹
β = 95.82 (3)°	T = 298 K
V = 1412.7 (5) Å³	Block, colorless
Z = 4	0.32 × 0.31 × 0.28 mm
F(000) = 776

Data collection top

Bruker APEX-II CCD diffractometer	R_int = 0.063
φ and ω scans	θ_max = 28.1°, θ_min = 3.1°
18639 measured reflections	h = −10→10
3402 independent reflections	k = −14→14
2697 reflections with I > 2σ(I)	l = −20→20

Refinement top

Refinement on F²	Hydrogen site location: mixed
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.047	w = 1/[σ²(F_o²) + (0.027P)² + 3.6916P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.103	(Δ/σ)_max < 0.001
S = 1.05	Δρ_max = 1.04 e Å⁻³
3402 reflections	Δρ_min = −1.11 e Å⁻³
183 parameters	Extinction correction: SHELXL-2014/7 (Sheldrick 2014, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0215 (12)

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Br1	0.30172 (6)	0.05663 (4)	0.53236 (3)	0.04660 (17)
Br2	0.56917 (7)	0.40130 (5)	0.77156 (3)	0.0568 (2)
O1	0.9542 (4)	0.6999 (2)	0.50139 (16)	0.0392 (7)
O2	0.7138 (4)	0.4993 (2)	0.62102 (17)	0.0398 (7)
H2A	0.7571	0.5246	0.5798	0.060*
N1	0.7758 (4)	0.5054 (3)	0.46549 (19)	0.0288 (7)
N2	0.8527 (4)	0.5622 (3)	0.40386 (19)	0.0295 (7)
H2B	0.8484	0.5342	0.3526	0.035*
N3	1.1114 (5)	0.8953 (3)	0.2380 (2)	0.0437 (9)
C1	0.5097 (5)	0.2521 (3)	0.4959 (2)	0.0302 (8)
H1	0.4958	0.2223	0.4402	0.036*
C2	0.4345 (5)	0.1947 (3)	0.5581 (2)	0.0303 (8)
C3	0.4518 (5)	0.2373 (3)	0.6411 (2)	0.0327 (8)
H3	0.4016	0.1975	0.6837	0.039*
C4	0.5451 (5)	0.3400 (3)	0.6593 (2)	0.0305 (8)
C5	0.6243 (5)	0.4005 (3)	0.5982 (2)	0.0277 (7)
C6	0.6067 (4)	0.3543 (3)	0.5143 (2)	0.0257 (7)
C7	0.6887 (5)	0.4117 (3)	0.4475 (2)	0.0300 (8)
H7	0.6775	0.3803	0.3922	0.036*
C8	0.9364 (4)	0.6653 (3)	0.4278 (2)	0.0262 (7)
C9	0.9994 (4)	0.7388 (3)	0.3583 (2)	0.0254 (7)
C10	1.1012 (5)	0.8349 (4)	0.3822 (2)	0.0376 (9)
H10	1.1336	0.8493	0.4396	0.045*
C11	1.1547 (6)	0.9091 (4)	0.3210 (3)	0.0457 (11)
H11	1.2252	0.9727	0.3385	0.055*
C12	1.0146 (7)	0.8029 (4)	0.2154 (3)	0.0500 (12)
H12	0.9838	0.7908	0.1576	0.060*
C13	0.9560 (6)	0.7225 (4)	0.2731 (2)	0.0417 (10)
H13	0.8879	0.6583	0.2540	0.050*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0549 (3)	0.0269 (2)	0.0594 (3)	−0.00864 (19)	0.0124 (2)	−0.00532 (19)
Br2	0.0984 (4)	0.0477 (3)	0.0268 (2)	−0.0061 (3)	0.0191 (2)	−0.00704 (18)
O1	0.068 (2)	0.0298 (14)	0.0206 (12)	−0.0016 (13)	0.0068 (13)	0.0014 (11)
O2	0.0606 (19)	0.0290 (14)	0.0307 (14)	−0.0108 (13)	0.0083 (13)	−0.0046 (11)
N1	0.0409 (18)	0.0205 (15)	0.0262 (15)	0.0043 (13)	0.0095 (13)	0.0048 (12)
N2	0.0459 (18)	0.0210 (14)	0.0236 (14)	0.0027 (13)	0.0139 (13)	0.0026 (11)
N3	0.062 (2)	0.0369 (19)	0.0342 (18)	−0.0021 (17)	0.0164 (17)	0.0093 (15)
C1	0.042 (2)	0.0219 (17)	0.0268 (17)	0.0051 (15)	0.0057 (15)	−0.0054 (14)
C2	0.0339 (19)	0.0194 (16)	0.039 (2)	0.0016 (15)	0.0087 (16)	−0.0002 (15)
C3	0.043 (2)	0.0241 (18)	0.0339 (19)	0.0060 (16)	0.0154 (17)	0.0038 (15)
C4	0.046 (2)	0.0228 (17)	0.0247 (17)	0.0070 (16)	0.0116 (16)	−0.0002 (14)
C5	0.038 (2)	0.0185 (16)	0.0272 (17)	0.0048 (14)	0.0056 (15)	−0.0012 (13)
C6	0.0355 (19)	0.0176 (15)	0.0252 (16)	0.0073 (14)	0.0086 (14)	0.0010 (13)
C7	0.040 (2)	0.0266 (18)	0.0244 (16)	0.0050 (15)	0.0088 (15)	0.0011 (14)
C8	0.037 (2)	0.0203 (16)	0.0221 (16)	0.0071 (14)	0.0061 (14)	0.0024 (13)
C9	0.0363 (19)	0.0192 (16)	0.0214 (15)	0.0054 (14)	0.0060 (14)	0.0016 (13)
C10	0.051 (2)	0.033 (2)	0.0275 (18)	−0.0050 (18)	−0.0019 (17)	0.0051 (16)
C11	0.053 (3)	0.036 (2)	0.047 (2)	−0.0127 (19)	0.005 (2)	0.0115 (19)
C12	0.087 (4)	0.040 (2)	0.0245 (19)	−0.006 (2)	0.011 (2)	0.0047 (17)
C13	0.073 (3)	0.029 (2)	0.0240 (18)	−0.011 (2)	0.0066 (19)	0.0011 (15)

Geometric parameters (Å, º) top

Br1—C2	1.884 (4)	C3—C4	1.374 (5)
Br2—C4	1.881 (4)	C3—H3	0.9300
O1—C8	1.213 (4)	C4—C5	1.384 (5)
O2—C5	1.336 (4)	C5—C6	1.406 (5)
O2—H2A	0.8200	C6—C7	1.451 (5)
N1—C7	1.266 (5)	C7—H7	0.9300
N1—N2	1.362 (4)	C8—C9	1.491 (5)
N2—C8	1.354 (5)	C9—C13	1.364 (5)
N2—H2B	0.8600	C9—C10	1.374 (5)
N3—C12	1.315 (6)	C10—C11	1.365 (6)
N3—C11	1.327 (6)	C10—H10	0.9300
C1—C2	1.364 (5)	C11—H11	0.9300
C1—C6	1.387 (5)	C12—C13	1.384 (6)
C1—H1	0.9300	C12—H12	0.9300
C2—C3	1.381 (5)	C13—H13	0.9300

C5—O2—H2A	109.5	C5—C6—C7	120.9 (3)
C7—N1—N2	120.3 (3)	N1—C7—C6	118.9 (3)
C8—N2—N1	116.3 (3)	N1—C7—H7	120.5
C8—N2—H2B	121.8	C6—C7—H7	120.5
N1—N2—H2B	121.8	O1—C8—N2	122.2 (3)
C12—N3—C11	116.7 (4)	O1—C8—C9	121.0 (3)
C2—C1—C6	121.0 (3)	N2—C8—C9	116.8 (3)
C2—C1—H1	119.5	C13—C9—C10	117.4 (3)
C6—C1—H1	119.5	C13—C9—C8	125.0 (3)
C1—C2—C3	120.9 (3)	C10—C9—C8	117.5 (3)
C1—C2—Br1	120.8 (3)	C11—C10—C9	119.6 (4)
C3—C2—Br1	118.3 (3)	C11—C10—H10	120.2
C4—C3—C2	118.3 (3)	C9—C10—H10	120.2
C4—C3—H3	120.9	N3—C11—C10	123.5 (4)
C2—C3—H3	120.9	N3—C11—H11	118.3
C3—C4—C5	122.7 (3)	C10—C11—H11	118.3
C3—C4—Br2	119.3 (3)	N3—C12—C13	123.6 (4)
C5—C4—Br2	118.0 (3)	N3—C12—H12	118.2
O2—C5—C4	119.1 (3)	C13—C12—H12	118.2
O2—C5—C6	122.9 (3)	C9—C13—C12	119.2 (4)
C4—C5—C6	118.0 (3)	C9—C13—H13	120.4
C1—C6—C5	119.2 (3)	C12—C13—H13	120.4
C1—C6—C7	119.9 (3)

(E)-N'-(3,5-dibromo-2-hydroxybenzylidene)isonicotinohydrazide (Compound-B-Form-II) top

Crystal data top

C₁₃H₉Br₂N₃O₂	F(000) = 776
M_r = 399.05	D_x = 1.855 Mg m⁻³
Triclinic, P1	Melting point: 519K K
a = 9.8084 (7) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.7751 (8) Å	Cell parameters from 4061 reflections
c = 13.9516 (9) Å	θ = 2.5–24.8°
α = 103.219 (3)°	µ = 5.68 mm⁻¹
β = 94.907 (3)°	T = 298 K
γ = 91.018 (3)°	Block, colorless
V = 1429.11 (17) Å³	0.32 × 0.31 × 0.30 mm
Z = 4

Data collection top

Bruker APEX-II CCD diffractometer	R_int = 0.055
φ and ω scans	θ_max = 24.8°, θ_min = 2.5°
28553 measured reflections	h = −11→11
4894 independent reflections	k = −12→12
4061 reflections with I > 2σ(I)	l = −16→16

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.048	H-atom parameters constrained
wR(F²) = 0.118	w = 1/[σ²(F_o²) + (0.032P)² + 4.3755P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max = 0.001
4894 reflections	Δρ_max = 1.52 e Å⁻³
363 parameters	Δρ_min = −1.40 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Br2	0.73509 (6)	0.00169 (6)	0.70559 (4)	0.06073 (18)
Br1	0.82119 (9)	−0.09189 (8)	0.30305 (5)	0.0966 (3)
O2	0.5507 (4)	0.2007 (3)	0.6517 (2)	0.0504 (8)
H2A	0.4914	0.2461	0.6349	0.076*
O1	0.2983 (4)	0.4772 (4)	0.6721 (3)	0.0576 (10)
N2	0.3399 (3)	0.4177 (3)	0.5124 (3)	0.0394 (9)
H2B	0.3278	0.4278	0.4570	0.047*
N3	−0.0206 (5)	0.7526 (4)	0.5262 (4)	0.0601 (12)
N1	0.4296 (3)	0.3282 (3)	0.5333 (3)	0.0375 (8)
C9	0.1745 (4)	0.5789 (4)	0.5601 (3)	0.0346 (9)
C5	0.6086 (4)	0.1379 (4)	0.5718 (3)	0.0347 (9)
C6	0.5821 (4)	0.1636 (4)	0.4778 (3)	0.0352 (9)
C8	0.2766 (4)	0.4872 (4)	0.5870 (3)	0.0380 (10)
C4	0.7000 (5)	0.0432 (4)	0.5818 (4)	0.0414 (10)
C3	0.7642 (5)	−0.0250 (4)	0.5030 (4)	0.0472 (12)
H3	0.8252	−0.0877	0.5112	0.057*
C7	0.4885 (4)	0.2625 (4)	0.4613 (3)	0.0383 (10)
H7	0.4720	0.2775	0.3984	0.046*
C1	0.6461 (5)	0.0955 (4)	0.3987 (4)	0.0455 (11)
H1	0.6288	0.1126	0.3365	0.055*
C10	0.1477 (5)	0.6033 (5)	0.4685 (4)	0.0471 (12)
H10	0.1946	0.5620	0.4159	0.057*
C2	0.7351 (5)	0.0028 (5)	0.4120 (4)	0.0499 (12)
C13	0.1007 (5)	0.6436 (5)	0.6352 (4)	0.0545 (13)
H13	0.1150	0.6299	0.6987	0.065*
C11	0.0499 (5)	0.6904 (5)	0.4553 (4)	0.0583 (14)
H11	0.0329	0.7059	0.3926	0.070*
C12	0.0058 (6)	0.7284 (6)	0.6142 (5)	0.0668 (16)
H12	−0.0427	0.7715	0.6653	0.080*
Br4	0.29171 (7)	0.84362 (8)	−0.14515 (5)	0.0840 (2)
Br3	0.86361 (8)	0.90562 (9)	−0.06147 (6)	0.0970 (3)
O4	0.3240 (3)	0.6773 (4)	−0.0025 (3)	0.0582 (10)
H4A	0.3316	0.6340	0.0388	0.087*
O3	0.3409 (4)	0.4193 (4)	0.3025 (3)	0.0596 (10)
N6	−0.0524 (5)	0.5975 (7)	0.1320 (4)	0.0793 (16)
N4	0.4527 (4)	0.5820 (4)	0.1330 (3)	0.0390 (8)
N5	0.4533 (4)	0.5158 (4)	0.2064 (3)	0.0444 (9)
H5B	0.5193	0.5084	0.2336	0.053*
C18	0.4463 (4)	0.7264 (5)	−0.0117 (3)	0.0410 (10)
C19	0.5679 (4)	0.7015 (5)	0.0403 (3)	0.0413 (10)
C22	0.2032 (5)	0.5236 (5)	0.1989 (3)	0.0444 (11)
C20	0.5663 (4)	0.6255 (5)	0.1147 (3)	0.0425 (11)
H00R	0.6476	0.6091	0.1482	0.051*
C21	0.3372 (5)	0.4820 (5)	0.2389 (3)	0.0443 (11)
C14	0.6924 (5)	0.7537 (6)	0.0234 (4)	0.0553 (13)
H14	0.7736	0.7363	0.0567	0.066*
C26	0.1814 (5)	0.6489 (5)	0.1949 (4)	0.0524 (12)
H26	0.2519	0.7108	0.2143	0.063*
C17	0.4543 (5)	0.8056 (5)	−0.0771 (4)	0.0512 (12)
C23	0.0948 (6)	0.4374 (6)	0.1712 (4)	0.0644 (15)
H23	0.1042	0.3527	0.1746	0.077*
C15	0.6947 (6)	0.8305 (6)	−0.0423 (4)	0.0611 (15)
C16	0.5767 (6)	0.8585 (5)	−0.0922 (4)	0.0615 (14)
H16	0.5797	0.9124	−0.1355	0.074*
C25	0.0528 (6)	0.6801 (7)	0.1614 (5)	0.0678 (16)
H25	0.0392	0.7647	0.1594	0.081*
C24	−0.0298 (6)	0.4794 (8)	0.1378 (5)	0.084 (2)
H24	−0.1024	0.4196	0.1182	0.101*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br2	0.0690 (4)	0.0634 (4)	0.0591 (3)	0.0242 (3)	0.0028 (3)	0.0330 (3)
Br1	0.1203 (6)	0.1085 (6)	0.0703 (4)	0.0789 (5)	0.0405 (4)	0.0228 (4)
O2	0.053 (2)	0.055 (2)	0.0454 (19)	0.0258 (16)	0.0073 (15)	0.0141 (16)
O1	0.052 (2)	0.082 (3)	0.044 (2)	0.0318 (19)	0.0012 (15)	0.0234 (18)
N2	0.0350 (19)	0.042 (2)	0.045 (2)	0.0190 (16)	0.0020 (16)	0.0185 (17)
N3	0.056 (3)	0.056 (3)	0.075 (3)	0.031 (2)	0.008 (2)	0.025 (2)
N1	0.0303 (18)	0.0338 (19)	0.051 (2)	0.0137 (15)	0.0015 (16)	0.0155 (17)
C9	0.026 (2)	0.033 (2)	0.045 (2)	0.0081 (17)	−0.0006 (17)	0.0113 (19)
C5	0.033 (2)	0.029 (2)	0.045 (3)	0.0083 (17)	0.0053 (18)	0.0126 (19)
C6	0.030 (2)	0.032 (2)	0.045 (3)	0.0087 (17)	0.0025 (18)	0.0106 (19)
C8	0.030 (2)	0.043 (3)	0.045 (3)	0.0090 (18)	0.0002 (18)	0.017 (2)
C4	0.039 (2)	0.037 (2)	0.054 (3)	0.0092 (19)	0.003 (2)	0.022 (2)
C3	0.041 (3)	0.040 (3)	0.065 (3)	0.020 (2)	0.009 (2)	0.020 (2)
C7	0.038 (2)	0.036 (2)	0.046 (3)	0.0112 (19)	0.0030 (19)	0.020 (2)
C1	0.047 (3)	0.046 (3)	0.048 (3)	0.017 (2)	0.007 (2)	0.018 (2)
C10	0.043 (3)	0.056 (3)	0.047 (3)	0.023 (2)	0.008 (2)	0.018 (2)
C2	0.052 (3)	0.048 (3)	0.054 (3)	0.023 (2)	0.017 (2)	0.015 (2)
C13	0.056 (3)	0.063 (3)	0.047 (3)	0.027 (3)	0.008 (2)	0.016 (2)
C11	0.054 (3)	0.065 (3)	0.064 (3)	0.028 (3)	0.003 (3)	0.032 (3)
C12	0.067 (4)	0.064 (4)	0.070 (4)	0.041 (3)	0.019 (3)	0.009 (3)
Br4	0.0747 (4)	0.1129 (6)	0.0794 (5)	0.0113 (4)	−0.0093 (3)	0.0585 (4)
Br3	0.0728 (5)	0.1145 (6)	0.1025 (6)	−0.0426 (4)	0.0219 (4)	0.0209 (5)
O4	0.0361 (18)	0.087 (3)	0.061 (2)	−0.0040 (17)	−0.0066 (15)	0.041 (2)
O3	0.067 (2)	0.073 (3)	0.050 (2)	0.0232 (19)	0.0154 (17)	0.0328 (19)
N6	0.041 (3)	0.128 (5)	0.081 (4)	0.011 (3)	0.002 (2)	0.051 (4)
N4	0.036 (2)	0.051 (2)	0.0327 (19)	0.0090 (17)	0.0012 (15)	0.0150 (17)
N5	0.036 (2)	0.062 (3)	0.039 (2)	0.0181 (18)	0.0019 (16)	0.0205 (19)
C18	0.037 (2)	0.051 (3)	0.034 (2)	−0.001 (2)	0.0002 (18)	0.011 (2)
C19	0.036 (2)	0.052 (3)	0.036 (2)	0.000 (2)	0.0016 (18)	0.009 (2)
C22	0.039 (2)	0.064 (3)	0.034 (2)	0.007 (2)	0.0069 (19)	0.017 (2)
C20	0.031 (2)	0.059 (3)	0.037 (2)	0.009 (2)	−0.0026 (18)	0.011 (2)
C21	0.049 (3)	0.053 (3)	0.033 (2)	0.016 (2)	0.006 (2)	0.012 (2)
C14	0.036 (3)	0.077 (4)	0.050 (3)	−0.007 (2)	−0.002 (2)	0.011 (3)
C26	0.044 (3)	0.060 (3)	0.055 (3)	0.012 (2)	0.006 (2)	0.016 (3)
C17	0.052 (3)	0.058 (3)	0.044 (3)	0.001 (2)	−0.003 (2)	0.015 (2)
C23	0.056 (3)	0.073 (4)	0.070 (4)	−0.003 (3)	0.005 (3)	0.029 (3)
C15	0.054 (3)	0.071 (4)	0.055 (3)	−0.019 (3)	0.010 (3)	0.009 (3)
C16	0.074 (4)	0.060 (3)	0.054 (3)	−0.013 (3)	0.010 (3)	0.019 (3)
C25	0.046 (3)	0.090 (5)	0.076 (4)	0.022 (3)	0.008 (3)	0.036 (3)
C24	0.047 (3)	0.123 (7)	0.085 (5)	−0.019 (4)	−0.006 (3)	0.035 (5)

Geometric parameters (Å, º) top

Br2—C4	1.886 (5)	Br4—C17	1.885 (5)
Br1—C2	1.899 (5)	Br3—C15	1.897 (5)
O2—C5	1.342 (5)	O4—C18	1.330 (5)
O2—H2A	0.8200	O4—H4A	0.8200
O1—C8	1.217 (5)	O3—C21	1.231 (6)
N2—C8	1.342 (6)	N6—C24	1.315 (9)
N2—N1	1.380 (4)	N6—C25	1.324 (8)
N2—H2B	0.8044	N4—C20	1.269 (6)
N3—C12	1.317 (7)	N4—N5	1.375 (5)
N3—C11	1.318 (7)	N5—C21	1.336 (6)
N1—C7	1.277 (6)	N5—H5B	0.7370
C9—C10	1.367 (6)	C18—C17	1.391 (7)
C9—C13	1.385 (6)	C18—C19	1.405 (6)
C9—C8	1.504 (5)	C19—C14	1.396 (7)
C5—C4	1.394 (6)	C19—C20	1.463 (7)
C5—C6	1.404 (6)	C22—C23	1.369 (7)
C6—C1	1.384 (6)	C22—C26	1.384 (7)
C6—C7	1.464 (5)	C22—C21	1.499 (6)
C4—C3	1.382 (7)	C20—H00R	0.9300
C3—C2	1.378 (7)	C14—C15	1.370 (8)
C3—H3	0.9300	C14—H14	0.9300
C7—H7	0.9300	C26—C25	1.382 (7)
C1—C2	1.373 (6)	C26—H26	0.9300
C1—H1	0.9300	C17—C16	1.373 (7)
C10—C11	1.384 (6)	C23—C24	1.390 (9)
C10—H10	0.9300	C23—H23	0.9300
C13—C12	1.377 (7)	C15—C16	1.374 (8)
C13—H13	0.9300	C16—H16	0.9300
C11—H11	0.9300	C25—H25	0.9300
C12—H12	0.9300	C24—H24	0.9300

C5—O2—H2A	109.5	C18—O4—H4A	109.5
C8—N2—N1	118.1 (4)	C24—N6—C25	116.0 (5)
C8—N2—H2B	122.0	C20—N4—N5	118.1 (4)
N1—N2—H2B	120.0	C21—N5—N4	121.6 (4)
C12—N3—C11	116.5 (4)	C21—N5—H5B	119.3
C7—N1—N2	117.3 (4)	N4—N5—H5B	118.4
C10—C9—C13	117.5 (4)	O4—C18—C17	118.2 (4)
C10—C9—C8	125.9 (4)	O4—C18—C19	123.5 (4)
C13—C9—C8	116.6 (4)	C17—C18—C19	118.2 (4)
O2—C5—C4	118.9 (4)	C14—C19—C18	119.6 (5)
O2—C5—C6	123.1 (4)	C14—C19—C20	119.1 (4)
C4—C5—C6	118.0 (4)	C18—C19—C20	121.3 (4)
C1—C6—C5	120.0 (4)	C23—C22—C26	117.9 (5)
C1—C6—C7	118.6 (4)	C23—C22—C21	119.5 (5)
C5—C6—C7	121.3 (4)	C26—C22—C21	122.4 (5)
O1—C8—N2	122.8 (4)	N4—C20—C19	119.3 (4)
O1—C8—C9	120.9 (4)	N4—C20—H00R	120.4
N2—C8—C9	116.3 (4)	C19—C20—H00R	120.4
C3—C4—C5	122.3 (4)	O3—C21—N5	120.0 (4)
C3—C4—Br2	118.1 (3)	O3—C21—C22	120.5 (4)
C5—C4—Br2	119.7 (4)	N5—C21—C22	119.5 (4)
C2—C3—C4	118.0 (4)	C15—C14—C19	119.8 (5)
C2—C3—H3	121.0	C15—C14—H14	120.1
C4—C3—H3	121.0	C19—C14—H14	120.1
N1—C7—C6	120.1 (4)	C25—C26—C22	118.6 (5)
N1—C7—H7	120.0	C25—C26—H26	120.7
C6—C7—H7	120.0	C22—C26—H26	120.7
C2—C1—C6	120.0 (4)	C16—C17—C18	122.0 (5)
C2—C1—H1	120.0	C16—C17—Br4	119.2 (4)
C6—C1—H1	120.0	C18—C17—Br4	118.9 (4)
C9—C10—C11	119.1 (5)	C22—C23—C24	118.5 (6)
C9—C10—H10	120.5	C22—C23—H23	120.8
C11—C10—H10	120.5	C24—C23—H23	120.8
C1—C2—C3	121.8 (4)	C14—C15—C16	121.6 (5)
C1—C2—Br1	119.9 (4)	C14—C15—Br3	119.5 (4)
C3—C2—Br1	118.2 (3)	C16—C15—Br3	118.9 (4)
C12—C13—C9	118.8 (5)	C17—C16—C15	118.8 (5)
C12—C13—H13	120.6	C17—C16—H16	120.6
C9—C13—H13	120.6	C15—C16—H16	120.6
N3—C11—C10	124.0 (5)	N6—C25—C26	124.3 (6)
N3—C11—H11	118.0	N6—C25—H25	117.9
C10—C11—H11	118.0	C26—C25—H25	117.9
N3—C12—C13	124.2 (5)	N6—C24—C23	124.6 (6)
N3—C12—H12	117.9	N6—C24—H24	117.7
C13—C12—H12	117.9	C23—C24—H24	117.7

C8—N2—N1—C7	179.7 (4)	C20—N4—N5—C21	170.9 (4)
O2—C5—C6—C1	179.6 (4)	O4—C18—C19—C14	177.8 (5)
C4—C5—C6—C1	0.1 (6)	C17—C18—C19—C14	−1.6 (7)
O2—C5—C6—C7	0.2 (7)	O4—C18—C19—C20	−4.3 (7)
C4—C5—C6—C7	−179.3 (4)	C17—C18—C19—C20	176.2 (4)
N1—N2—C8—O1	2.4 (7)	N5—N4—C20—C19	−177.0 (4)
N1—N2—C8—C9	−177.0 (4)	C14—C19—C20—N4	177.3 (5)
C10—C9—C8—O1	176.0 (5)	C18—C19—C20—N4	−0.6 (7)
C13—C9—C8—O1	−4.4 (7)	N4—N5—C21—O3	177.6 (4)
C10—C9—C8—N2	−4.5 (7)	N4—N5—C21—C22	−3.7 (7)
C13—C9—C8—N2	175.0 (4)	C23—C22—C21—O3	−46.7 (7)
O2—C5—C4—C3	−179.6 (4)	C26—C22—C21—O3	128.8 (5)
C6—C5—C4—C3	0.0 (7)	C23—C22—C21—N5	134.6 (5)
O2—C5—C4—Br2	2.2 (6)	C26—C22—C21—N5	−49.9 (7)
C6—C5—C4—Br2	−178.2 (3)	C18—C19—C14—C15	1.3 (8)
C5—C4—C3—C2	−0.2 (7)	C20—C19—C14—C15	−176.7 (5)
Br2—C4—C3—C2	178.0 (4)	C23—C22—C26—C25	−1.3 (8)
N2—N1—C7—C6	−178.4 (4)	C21—C22—C26—C25	−176.9 (5)
C1—C6—C7—N1	−178.9 (4)	O4—C18—C17—C16	−179.0 (5)
C5—C6—C7—N1	0.5 (7)	C19—C18—C17—C16	0.5 (8)
C5—C6—C1—C2	0.1 (7)	O4—C18—C17—Br4	2.1 (7)
C7—C6—C1—C2	179.6 (5)	C19—C18—C17—Br4	−178.4 (4)
C13—C9—C10—C11	0.1 (8)	C26—C22—C23—C24	1.9 (8)
C8—C9—C10—C11	179.7 (5)	C21—C22—C23—C24	177.6 (5)
C6—C1—C2—C3	−0.4 (8)	C19—C14—C15—C16	0.3 (9)
C6—C1—C2—Br1	179.3 (4)	C19—C14—C15—Br3	177.9 (4)
C4—C3—C2—C1	0.4 (8)	C18—C17—C16—C15	1.0 (9)
C4—C3—C2—Br1	−179.2 (4)	Br4—C17—C16—C15	179.9 (4)
C10—C9—C13—C12	−0.3 (8)	C14—C15—C16—C17	−1.4 (9)
C8—C9—C13—C12	−179.9 (5)	Br3—C15—C16—C17	−179.0 (4)
C12—N3—C11—C10	0.0 (9)	C24—N6—C25—C26	1.3 (10)
C9—C10—C11—N3	0.0 (9)	C22—C26—C25—N6	−0.4 (9)
C11—N3—C12—C13	−0.1 (10)	C25—N6—C24—C23	−0.6 (11)
C9—C13—C12—N3	0.3 (10)	C22—C23—C24—N6	−1.0 (11)

(E)-N'-(3-bromo-5-chloro-2-hydroxybenzylidene)isonicotinohydrazide (Compound-C-Form-I) top

Crystal data top

C₁₃H₉BrClN₃O₂	D_x = 1.683 Mg m⁻³
M_r = 354.59	Melting point: 528K K
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.2475 (9) Å	Cell parameters from 2198 reflections
b = 10.8035 (11) Å	θ = 2.3–25.0°
c = 15.7971 (15) Å	µ = 3.13 mm⁻¹
β = 96.098 (3)°	T = 298 K
V = 1399.6 (2) Å³	Block, colorless
Z = 4	0.32 × 0.31 × 0.28 mm
F(000) = 704

Data collection top

Bruker APEX-II CCD diffractometer	R_int = 0.046
φ and ω scans	θ_max = 25.0°, θ_min = 2.3°
10084 measured reflections	h = −9→9
2457 independent reflections	k = −12→12
2198 reflections with I > 2σ(I)	l = −18→18

Refinement top

Refinement on F²	Hydrogen site location: mixed
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.035	w = 1/[σ²(F_o²) + (0.0498P)² + 0.7988P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.099	(Δ/σ)_max < 0.001
S = 1.08	Δρ_max = 0.43 e Å⁻³
2457 reflections	Δρ_min = −0.54 e Å⁻³
183 parameters	Extinction correction: SHELXL-2014/7 (Sheldrick 2014, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.022 (2)

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Br1	0.41816 (5)	0.40191 (3)	0.22492 (2)	0.0610 (2)
Cl1	0.67518 (9)	0.06570 (7)	0.46488 (5)	0.0507 (2)
O1	0.0405 (3)	0.71406 (18)	0.49314 (11)	0.0450 (5)
O2	0.2761 (3)	0.50526 (18)	0.37543 (12)	0.0449 (5)
H2A	0.2415	0.5365	0.4173	0.067*
N2	0.1425 (3)	0.57691 (19)	0.59304 (14)	0.0328 (5)
H2B	0.1481	0.5507	0.6447	0.039*
N1	0.2171 (3)	0.5159 (2)	0.53150 (13)	0.0335 (5)
N3	−0.1195 (3)	0.9179 (2)	0.75562 (16)	0.0452 (6)
C9	−0.0040 (3)	0.7583 (2)	0.63618 (15)	0.0300 (5)
C6	0.3831 (3)	0.3596 (2)	0.48340 (15)	0.0298 (5)
C5	0.3651 (3)	0.4048 (2)	0.39932 (17)	0.0317 (5)
C4	0.4427 (3)	0.3412 (2)	0.33786 (16)	0.0347 (6)
C1	0.4798 (3)	0.2549 (2)	0.50300 (16)	0.0338 (5)
H1	0.4936	0.2251	0.5586	0.041*
C7	0.3039 (3)	0.4207 (2)	0.55082 (17)	0.0333 (6)
H7	0.3167	0.3906	0.6063	0.040*
C8	0.0593 (3)	0.6810 (2)	0.56748 (16)	0.0323 (5)
C3	0.5357 (3)	0.2370 (2)	0.35713 (17)	0.0365 (6)
H3	0.5847	0.1956	0.3150	0.044*
C2	0.5548 (3)	0.1954 (2)	0.44023 (18)	0.0355 (6)
C10	0.0316 (4)	0.7389 (3)	0.72229 (18)	0.0470 (7)
H10	0.0951	0.6717	0.7421	0.056*
C13	−0.0984 (4)	0.8591 (3)	0.61145 (18)	0.0448 (7)
H13	−0.1247	0.8761	0.5539	0.054*
C11	−0.0282 (4)	0.8206 (3)	0.77902 (18)	0.0501 (7)
H11	−0.0027	0.8061	0.8369	0.060*
C12	−0.1540 (4)	0.9348 (3)	0.6720 (2)	0.0514 (8)
H12	−0.2195	1.0017	0.6536	0.062*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.1058 (4)	0.0508 (3)	0.0292 (2)	0.00423 (16)	0.02044 (18)	0.00664 (12)
Cl1	0.0557 (4)	0.0373 (4)	0.0598 (5)	0.0116 (3)	0.0096 (3)	0.0038 (3)
O1	0.0707 (13)	0.0408 (11)	0.0235 (9)	0.0007 (9)	0.0052 (9)	−0.0035 (8)
O2	0.0656 (12)	0.0358 (10)	0.0337 (10)	0.0133 (9)	0.0079 (9)	0.0045 (8)
N2	0.0455 (12)	0.0286 (11)	0.0258 (10)	−0.0012 (9)	0.0109 (9)	−0.0025 (8)
N1	0.0412 (11)	0.0298 (11)	0.0310 (11)	−0.0056 (9)	0.0108 (9)	−0.0064 (9)
N3	0.0614 (15)	0.0397 (14)	0.0354 (13)	0.0031 (11)	0.0096 (11)	−0.0100 (10)
C9	0.0379 (12)	0.0262 (12)	0.0261 (12)	−0.0058 (10)	0.0040 (9)	−0.0030 (10)
C6	0.0356 (12)	0.0269 (12)	0.0278 (12)	−0.0058 (10)	0.0079 (10)	−0.0019 (10)
C5	0.0402 (13)	0.0237 (12)	0.0313 (13)	−0.0043 (9)	0.0046 (10)	−0.0008 (10)
C4	0.0477 (14)	0.0317 (13)	0.0258 (12)	−0.0080 (11)	0.0090 (11)	−0.0012 (11)
C1	0.0426 (13)	0.0298 (13)	0.0298 (13)	−0.0034 (10)	0.0072 (10)	0.0037 (10)
C7	0.0417 (13)	0.0311 (13)	0.0285 (13)	−0.0054 (11)	0.0097 (10)	−0.0023 (10)
C8	0.0395 (13)	0.0307 (13)	0.0270 (12)	−0.0090 (10)	0.0054 (10)	−0.0047 (10)
C3	0.0454 (14)	0.0289 (13)	0.0372 (14)	−0.0034 (11)	0.0142 (11)	−0.0038 (11)
C2	0.0369 (13)	0.0273 (13)	0.0434 (15)	−0.0025 (10)	0.0093 (11)	0.0012 (11)
C10	0.080 (2)	0.0323 (14)	0.0289 (14)	0.0105 (14)	0.0072 (13)	−0.0022 (11)
C13	0.0594 (17)	0.0454 (16)	0.0286 (14)	0.0092 (14)	−0.0009 (12)	−0.0037 (13)
C11	0.082 (2)	0.0434 (16)	0.0256 (13)	0.0037 (15)	0.0109 (14)	−0.0018 (12)
C12	0.0646 (19)	0.0478 (17)	0.0407 (16)	0.0188 (15)	0.0011 (14)	−0.0066 (14)

Geometric parameters (Å, º) top

Br1—C4	1.892 (3)	C6—C5	1.408 (4)
Cl1—C2	1.737 (3)	C6—C7	1.464 (3)
O1—C8	1.221 (3)	C5—C4	1.399 (4)
O2—C5	1.342 (3)	C4—C3	1.377 (4)
O2—H2A	0.8200	C1—C2	1.382 (4)
N2—C8	1.356 (3)	C1—H1	0.9300
N2—N1	1.373 (3)	C7—H7	0.9300
N2—H2B	0.8600	C3—C2	1.381 (4)
N1—C7	1.272 (3)	C3—H3	0.9300
N3—C11	1.323 (4)	C10—C11	1.385 (4)
N3—C12	1.334 (4)	C10—H10	0.9300
C9—C13	1.371 (4)	C13—C12	1.374 (4)
C9—C10	1.377 (4)	C13—H13	0.9300
C9—C8	1.506 (3)	C11—H11	0.9300
C6—C1	1.400 (4)	C12—H12	0.9300

C5—O2—H2A	109.5	C6—C7—H7	120.9
C8—N2—N1	115.9 (2)	O1—C8—N2	122.5 (2)
C8—N2—H2B	122.0	O1—C8—C9	120.8 (2)
N1—N2—H2B	122.0	N2—C8—C9	116.6 (2)
C7—N1—N2	120.1 (2)	C4—C3—C2	118.7 (2)
C11—N3—C12	116.2 (2)	C4—C3—H3	120.6
C13—C9—C10	117.2 (2)	C2—C3—H3	120.6
C13—C9—C8	117.7 (2)	C3—C2—C1	121.1 (2)
C10—C9—C8	125.0 (2)	C3—C2—Cl1	118.7 (2)
C1—C6—C5	119.3 (2)	C1—C2—Cl1	120.2 (2)
C1—C6—C7	119.4 (2)	C9—C10—C11	119.3 (3)
C5—C6—C7	121.3 (2)	C9—C10—H10	120.4
O2—C5—C4	118.6 (2)	C11—C10—H10	120.4
O2—C5—C6	123.1 (2)	C9—C13—C12	119.8 (3)
C4—C5—C6	118.3 (2)	C9—C13—H13	120.1
C3—C4—C5	122.2 (2)	C12—C13—H13	120.1
C3—C4—Br1	119.55 (18)	N3—C11—C10	123.8 (3)
C5—C4—Br1	118.2 (2)	N3—C11—H11	118.1
C2—C1—C6	120.3 (2)	C10—C11—H11	118.1
C2—C1—H1	119.8	N3—C12—C13	123.7 (3)
C6—C1—H1	119.8	N3—C12—H12	118.1
N1—C7—C6	118.2 (2)	C13—C12—H12	118.1
N1—C7—H7	120.9

(E)-N'-(3-bromo-5-chloro-2-hydroxybenzylidene)isonicotinohydrazide (Compound-C-Form-II) top

Crystal data top

C₁₃H₉BrClN₃O₂	D_x = 1.667 Mg m⁻³
M_r = 354.59	Melting point: 528K K
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.651 (2) Å	Cell parameters from 2117 reflections
b = 10.446 (3) Å	θ = 2.4–28.9°
c = 15.680 (4) Å	µ = 3.10 mm⁻¹
β = 94.116 (11)°	T = 368 K
V = 1413.3 (7) Å³	Block, colorless
Z = 4	0.32 × 0.31 × 0.31 mm
F(000) = 704

Data collection top

Bruker APEX-II CCD diffractometer	R_int = 0.060
φ and ω scans	θ_max = 28.9°, θ_min = 2.4°
23004 measured reflections	h = −11→11
3582 independent reflections	k = −13→14
2117 reflections with I > 2σ(I)	l = −21→21

Refinement top

Refinement on F²	Hydrogen site location: mixed
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.088	w = 1/[σ²(F_o²) + (0.1107P)²] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.202	(Δ/σ)_max = 0.001
S = 1.14	Δρ_max = 1.16 e Å⁻³
3582 reflections	Δρ_min = −1.49 e Å⁻³
183 parameters	Extinction correction: SHELXL-2014/7 (Sheldrick 2014, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.236 (14)

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Br1	0.59464 (8)	0.59293 (5)	0.78291 (2)	0.0971 (3)
Cl1	0.34046 (14)	0.90960 (11)	0.53112 (8)	0.0845 (4)
O2	0.7401 (4)	0.4781 (3)	0.63450 (16)	0.0781 (8)
H2A	0.7898	0.4533	0.5951	0.117*
O1	0.9911 (3)	0.2631 (3)	0.51524 (15)	0.0771 (8)
N1	0.8035 (3)	0.4577 (3)	0.47757 (18)	0.0596 (7)
N2	0.8754 (4)	0.3932 (3)	0.41538 (19)	0.0602 (7)
H2B	0.8642	0.4161	0.3626	0.072*
N3	1.1352 (4)	0.0517 (4)	0.2466 (2)	0.0722 (9)
C7	0.7150 (4)	0.5508 (4)	0.4564 (2)	0.0577 (8)
H7	0.7014	0.5766	0.3996	0.069*
C6	0.6348 (4)	0.6170 (3)	0.5220 (2)	0.0540 (8)
C4	0.5707 (5)	0.6448 (4)	0.6676 (2)	0.0614 (8)
C1	0.5402 (4)	0.7193 (4)	0.4994 (2)	0.0595 (8)
H1	0.5286	0.7455	0.4426	0.071*
C2	0.4626 (4)	0.7833 (3)	0.5604 (2)	0.0593 (8)
C8	0.9650 (4)	0.2916 (4)	0.4407 (2)	0.0578 (8)
C5	0.6505 (4)	0.5772 (3)	0.6080 (2)	0.0571 (8)
C9	1.0255 (4)	0.2134 (3)	0.37040 (19)	0.0552 (8)
C11	1.0603 (6)	0.1566 (5)	0.2263 (2)	0.0779 (12)
H11	1.0448	0.1770	0.1686	0.093*
C13	1.1056 (6)	0.1051 (4)	0.3923 (3)	0.0835 (14)
H13	1.1244	0.0830	0.4496	0.100*
C3	0.4784 (4)	0.7470 (4)	0.6450 (2)	0.0619 (9)
H3	0.4271	0.7913	0.6859	0.074*
C12	1.1587 (7)	0.0285 (6)	0.3298 (3)	0.0963 (17)
H12	1.2147	−0.0443	0.3467	0.116*
C10	1.0027 (6)	0.2393 (4)	0.2843 (2)	0.0792 (12)
H10	0.9488	0.3122	0.2656	0.095*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.1592 (6)	0.0880 (5)	0.0465 (3)	0.0093 (3)	0.0241 (3)	0.00634 (18)
Cl1	0.0857 (7)	0.0798 (8)	0.0875 (8)	0.0181 (5)	0.0031 (6)	0.0038 (5)
O2	0.106 (2)	0.0728 (19)	0.0565 (14)	0.0243 (16)	0.0133 (13)	0.0043 (13)
O1	0.103 (2)	0.085 (2)	0.0437 (13)	0.0044 (16)	0.0050 (12)	−0.0066 (12)
N1	0.0667 (17)	0.0612 (17)	0.0531 (15)	−0.0062 (15)	0.0179 (12)	−0.0108 (14)
N2	0.0737 (17)	0.0615 (18)	0.0473 (15)	−0.0032 (15)	0.0184 (13)	−0.0058 (12)
N3	0.089 (2)	0.074 (2)	0.0538 (17)	0.0112 (19)	0.0067 (15)	−0.0115 (16)
C7	0.0666 (19)	0.061 (2)	0.0460 (16)	−0.0072 (17)	0.0113 (14)	−0.0048 (15)
C6	0.0591 (17)	0.0563 (19)	0.0476 (16)	−0.0116 (15)	0.0106 (13)	−0.0019 (13)
C4	0.082 (2)	0.0579 (19)	0.0454 (16)	−0.0082 (18)	0.0133 (14)	−0.0030 (15)
C1	0.0669 (18)	0.064 (2)	0.0476 (16)	−0.0079 (17)	0.0065 (14)	0.0033 (15)
C2	0.0643 (18)	0.0529 (18)	0.0609 (19)	−0.0020 (16)	0.0067 (14)	−0.0022 (16)
C8	0.0694 (19)	0.0587 (19)	0.0459 (16)	−0.0102 (16)	0.0085 (13)	−0.0082 (14)
C5	0.0691 (19)	0.0544 (19)	0.0487 (17)	−0.0043 (16)	0.0103 (14)	−0.0018 (14)
C9	0.0644 (18)	0.0591 (19)	0.0424 (15)	−0.0070 (15)	0.0052 (13)	−0.0072 (14)
C11	0.119 (3)	0.072 (3)	0.0430 (17)	0.010 (3)	0.0092 (18)	−0.0045 (18)
C13	0.112 (3)	0.093 (3)	0.0451 (19)	0.031 (3)	0.000 (2)	−0.0032 (18)
C3	0.071 (2)	0.059 (2)	0.0576 (18)	−0.0078 (17)	0.0171 (15)	−0.0088 (15)
C12	0.135 (4)	0.096 (4)	0.058 (2)	0.051 (3)	0.003 (2)	−0.005 (2)
C10	0.124 (4)	0.065 (2)	0.0487 (19)	0.017 (2)	0.0113 (19)	0.0011 (17)

Geometric parameters (Å, º) top

Br1—C4	1.885 (3)	C4—C3	1.364 (5)
Cl1—C2	1.731 (4)	C4—C5	1.394 (5)
O2—C5	1.341 (4)	C1—C2	1.381 (5)
O2—H2A	0.8200	C1—H1	0.9300
O1—C8	1.211 (4)	C2—C3	1.376 (5)
N1—C7	1.267 (5)	C8—C9	1.497 (5)
N1—N2	1.371 (4)	C9—C13	1.359 (5)
N2—C8	1.356 (5)	C9—C10	1.376 (5)
N2—H2B	0.8600	C11—C10	1.374 (6)
N3—C11	1.300 (6)	C11—H11	0.9300
N3—C12	1.329 (5)	C13—C12	1.369 (6)
C7—C6	1.456 (5)	C13—H13	0.9300
C7—H7	0.9300	C3—H3	0.9300
C6—C1	1.377 (5)	C12—H12	0.9300
C6—C5	1.408 (5)	C10—H10	0.9300

C5—O2—H2A	109.5	N2—C8—C9	115.7 (3)
C7—N1—N2	119.2 (3)	O2—C5—C4	119.1 (3)
C8—N2—N1	117.1 (3)	O2—C5—C6	122.6 (3)
C8—N2—H2B	121.5	C4—C5—C6	118.3 (3)
N1—N2—H2B	121.5	C13—C9—C10	116.5 (3)
C11—N3—C12	115.7 (4)	C13—C9—C8	117.9 (3)
N1—C7—C6	119.2 (3)	C10—C9—C8	125.6 (3)
N1—C7—H7	120.4	N3—C11—C10	124.5 (4)
C6—C7—H7	120.4	N3—C11—H11	117.8
C1—C6—C5	119.4 (3)	C10—C11—H11	117.8
C1—C6—C7	119.4 (3)	C9—C13—C12	119.8 (4)
C5—C6—C7	121.2 (3)	C9—C13—H13	120.1
C3—C4—C5	122.0 (3)	C12—C13—H13	120.1
C3—C4—Br1	119.8 (3)	C4—C3—C2	118.9 (3)
C5—C4—Br1	118.2 (3)	C4—C3—H3	120.6
C6—C1—C2	120.4 (3)	C2—C3—H3	120.6
C6—C1—H1	119.8	N3—C12—C13	124.1 (4)
C2—C1—H1	119.8	N3—C12—H12	118.0
C3—C2—C1	121.0 (3)	C13—C12—H12	118.0
C3—C2—Cl1	118.8 (3)	C11—C10—C9	119.5 (4)
C1—C2—Cl1	120.2 (3)	C11—C10—H10	120.2
O1—C8—N2	122.6 (3)	C9—C10—H10	120.2
O1—C8—C9	121.7 (3)

(E)-N'-(3,5-diiodo-2-hydroxybenzylidene)isonicotinohydrazide (Compound-D) top

Crystal data top

C₁₃H₉I₂N₃O₂	D_x = 2.182 Mg m⁻³
M_r = 493.03	Melting point: 517K K
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 8.2946 (5) Å	Cell parameters from 2357 reflections
b = 11.2673 (6) Å	θ = 2.2–25.0°
c = 16.2177 (10) Å	µ = 4.19 mm⁻¹
β = 97.993 (2)°	T = 298 K
V = 1500.95 (15) Å³	Block, colorless
Z = 4	0.29 × 0.28 × 0.27 mm
F(000) = 920

Data collection top

Bruker APEX-II CCD diffractometer	R_int = 0.023
φ and ω scans	θ_max = 25.0°, θ_min = 2.2°
9640 measured reflections	h = −9→9
2587 independent reflections	k = −13→13
2357 reflections with I > 2σ(I)	l = −19→19

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.027	H-atom parameters constrained
wR(F²) = 0.070	w = 1/[σ²(F_o²) + (0.0265P)² + 3.1834P] where P = (F_o² + 2F_c²)/3
S = 1.11	(Δ/σ)_max = 0.001
2587 reflections	Δρ_max = 1.02 e Å⁻³
182 parameters	Δρ_min = −0.96 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
I2	0.58554 (4)	0.41683 (3)	0.76672 (2)	0.05257 (12)
I1	0.27549 (4)	0.05821 (2)	0.51862 (2)	0.05121 (12)
O2	0.7222 (4)	0.4972 (2)	0.60700 (17)	0.0413 (6)
H2A	0.7606	0.5230	0.5652	0.062*
O1	0.9562 (4)	0.6882 (2)	0.48897 (16)	0.0441 (7)
N2	0.8490 (4)	0.5518 (3)	0.3942 (2)	0.0342 (7)
H2B	0.8428	0.5223	0.3436	0.041*
N1	0.7737 (4)	0.4997 (3)	0.45472 (19)	0.0343 (7)
C7	0.6862 (5)	0.4077 (3)	0.4376 (2)	0.0338 (8)
H7	0.6740	0.3737	0.3835	0.041*
N3	1.0956 (5)	0.8752 (3)	0.2307 (2)	0.0496 (9)
C6	0.6049 (4)	0.3559 (3)	0.5034 (2)	0.0304 (7)
C5	0.6276 (4)	0.4026 (3)	0.5850 (2)	0.0314 (8)
C3	0.4507 (5)	0.2496 (3)	0.6278 (2)	0.0360 (8)
H3	0.3995	0.2131	0.6701	0.043*
C9	0.9929 (4)	0.7230 (3)	0.3485 (2)	0.0320 (8)
C2	0.4276 (4)	0.2054 (3)	0.5469 (2)	0.0349 (8)
C4	0.5491 (5)	0.3474 (3)	0.6453 (2)	0.0329 (8)
C8	0.9341 (4)	0.6523 (3)	0.4173 (2)	0.0323 (8)
C1	0.5037 (5)	0.2577 (3)	0.4856 (2)	0.0346 (8)
H1	0.4870	0.2264	0.4306	0.042*
C13	1.1029 (5)	0.8125 (4)	0.3715 (3)	0.0422 (9)
H13	1.1445	0.8242	0.4285	0.051*
C10	0.9352 (5)	0.7110 (4)	0.2650 (3)	0.0450 (10)
H10	0.8594	0.6501	0.2464	0.054*
C11	0.9888 (6)	0.7887 (4)	0.2084 (3)	0.0530 (11)
H11	0.9477	0.7799	0.1511	0.064*
C12	1.1521 (6)	0.8848 (4)	0.3116 (3)	0.0483 (10)
H12	1.2304	0.9446	0.3286	0.058*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
I2	0.0763 (2)	0.05289 (19)	0.03100 (16)	−0.00126 (15)	0.01636 (13)	−0.00489 (12)
I1	0.0582 (2)	0.03335 (17)	0.0645 (2)	−0.00889 (12)	0.01721 (15)	−0.00518 (12)
O2	0.0519 (16)	0.0365 (14)	0.0368 (14)	−0.0086 (13)	0.0109 (12)	−0.0023 (12)
O1	0.0614 (18)	0.0416 (15)	0.0303 (14)	−0.0007 (13)	0.0097 (12)	0.0008 (12)
N2	0.0427 (18)	0.0305 (16)	0.0329 (16)	0.0019 (13)	0.0171 (14)	0.0030 (13)
N1	0.0423 (17)	0.0317 (16)	0.0318 (16)	0.0050 (14)	0.0158 (13)	0.0054 (13)
C7	0.042 (2)	0.0309 (18)	0.0307 (19)	0.0048 (16)	0.0132 (16)	0.0024 (15)
N3	0.061 (2)	0.044 (2)	0.048 (2)	−0.0030 (18)	0.0223 (18)	0.0108 (17)
C6	0.0357 (18)	0.0264 (17)	0.0308 (18)	0.0057 (15)	0.0110 (15)	0.0046 (14)
C5	0.0362 (19)	0.0258 (17)	0.0329 (19)	0.0046 (15)	0.0069 (15)	0.0013 (14)
C3	0.043 (2)	0.0316 (19)	0.036 (2)	0.0080 (16)	0.0166 (16)	0.0057 (16)
C9	0.0343 (18)	0.0274 (17)	0.0360 (19)	0.0058 (15)	0.0111 (15)	0.0033 (15)
C2	0.0364 (19)	0.0259 (17)	0.045 (2)	0.0014 (15)	0.0143 (16)	0.0012 (16)
C4	0.041 (2)	0.0325 (19)	0.0266 (18)	0.0067 (16)	0.0110 (15)	−0.0007 (14)
C8	0.0362 (19)	0.0299 (18)	0.0319 (19)	0.0080 (15)	0.0093 (15)	0.0041 (15)
C1	0.043 (2)	0.0303 (18)	0.0317 (19)	0.0046 (16)	0.0090 (16)	−0.0038 (15)
C13	0.050 (2)	0.038 (2)	0.038 (2)	−0.0028 (18)	0.0045 (18)	0.0053 (17)
C10	0.058 (3)	0.043 (2)	0.034 (2)	−0.014 (2)	0.0078 (18)	0.0020 (18)
C11	0.072 (3)	0.054 (3)	0.034 (2)	−0.007 (2)	0.014 (2)	0.005 (2)
C12	0.052 (2)	0.040 (2)	0.053 (3)	−0.010 (2)	0.008 (2)	0.0082 (19)

Geometric parameters (Å, º) top

I2—C4	2.102 (4)	C5—C4	1.394 (5)
I1—C2	2.096 (4)	C3—C4	1.376 (5)
O2—C5	1.342 (5)	C3—C2	1.391 (5)
O2—H2A	0.8400	C3—H3	0.9500
O1—C8	1.220 (5)	C9—C13	1.376 (6)
N2—C8	1.359 (5)	C9—C10	1.380 (6)
N2—N1	1.367 (4)	C9—C8	1.507 (5)
N2—H2B	0.8800	C2—C1	1.382 (5)
N1—C7	1.274 (5)	C1—H1	0.9500
C7—C6	1.461 (5)	C13—C12	1.372 (6)
C7—H7	0.9500	C13—H13	0.9500
N3—C11	1.333 (6)	C10—C11	1.386 (6)
N3—C12	1.335 (6)	C10—H10	0.9500
C6—C1	1.395 (5)	C11—H11	0.9500
C6—C5	1.412 (5)	C12—H12	0.9500

C5—O2—H2A	109.5	C3—C2—I1	119.3 (3)
C8—N2—N1	115.5 (3)	C3—C4—C5	122.3 (3)
C8—N2—H2B	122.2	C3—C4—I2	119.7 (3)
N1—N2—H2B	122.2	C5—C4—I2	118.1 (3)
C7—N1—N2	119.8 (3)	O1—C8—N2	122.9 (3)
N1—C7—C6	118.2 (3)	O1—C8—C9	120.6 (3)
N1—C7—H7	120.9	N2—C8—C9	116.4 (3)
C6—C7—H7	120.9	C2—C1—C6	120.7 (3)
C11—N3—C12	117.1 (4)	C2—C1—H1	119.6
C1—C6—C5	119.2 (3)	C6—C1—H1	119.6
C1—C6—C7	119.4 (3)	C12—C13—C9	119.7 (4)
C5—C6—C7	121.4 (3)	C12—C13—H13	120.2
O2—C5—C4	118.7 (3)	C9—C13—H13	120.2
O2—C5—C6	122.8 (3)	C9—C10—C11	119.3 (4)
C4—C5—C6	118.4 (3)	C9—C10—H10	120.4
C4—C3—C2	118.7 (3)	C11—C10—H10	120.4
C4—C3—H3	120.6	N3—C11—C10	123.0 (4)
C2—C3—H3	120.6	N3—C11—H11	118.5
C13—C9—C10	117.7 (4)	C10—C11—H11	118.5
C13—C9—C8	117.2 (3)	N3—C12—C13	123.3 (4)
C10—C9—C8	124.9 (3)	N3—C12—H12	118.4
C1—C2—C3	120.6 (3)	C13—C12—H12	118.4
C1—C2—I1	120.1 (3)

(E)-N'-(3,5-difluoro-2-hydroxybenzylidene)isonicotinohydrazide (Compound-E) top

Crystal data top

C₁₃H₉F₂N₃O₂	D_x = 1.498 Mg m⁻³
M_r = 277.23	Melting point: 560K K
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71075 Å
a = 7.897 (2) Å	Cell parameters from 1807 reflections
b = 10.396 (2) Å	θ = 2.6–26.0°
c = 14.989 (3) Å	µ = 0.12 mm⁻¹
β = 92.27 (3)°	T = 298 K
V = 1229.6 (5) Å³	Block, colorless
Z = 4	0.32 × 0.31 × 0.29 mm
F(000) = 568

Data collection top

Bruker APEX-II CCD diffractometer	R_int = 0.054
φ and ω scans	θ_max = 26.0°, θ_min = 2.6°
30614 measured reflections	h = −9→9
2336 independent reflections	k = −12→12
1807 reflections with I > 2σ(I)	l = −18→18

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.046	H-atom parameters constrained
wR(F²) = 0.123	w = 1/[σ²(F_o²) + (0.0626P)² + 0.307P] where P = (F_o² + 2F_c²)/3
S = 1.10	(Δ/σ)_max < 0.001
2336 reflections	Δρ_max = 0.19 e Å⁻³
182 parameters	Δρ_min = −0.28 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O1	0.42881 (18)	0.73722 (13)	0.46767 (8)	0.0486 (4)
F1	−0.14254 (16)	0.04523 (11)	0.43995 (9)	0.0635 (4)
N3	0.6382 (2)	0.95941 (14)	0.74940 (10)	0.0391 (4)
C5	0.1172 (2)	0.37279 (17)	0.36732 (11)	0.0350 (4)
N1	0.27153 (18)	0.51969 (14)	0.50683 (9)	0.0338 (4)
C3	−0.0462 (2)	0.1805 (2)	0.32656 (13)	0.0464 (5)
H2	−0.0953	0.1271	0.2830	0.056*
O2	0.19743 (19)	0.47943 (14)	0.33815 (9)	0.0517 (4)
H2A	0.2488	0.5140	0.3803	0.078*
F2	0.04871 (19)	0.32311 (15)	0.21666 (7)	0.0733 (5)
N2	0.34617 (18)	0.59524 (14)	0.57290 (9)	0.0339 (4)
H2B	0.3446	0.5738	0.6283	0.041*
C4	0.0387 (3)	0.2910 (2)	0.30446 (12)	0.0440 (5)
C1	0.0195 (2)	0.22795 (17)	0.48215 (12)	0.0368 (4)
H1	0.0115	0.2055	0.5419	0.044*
C2	−0.0549 (2)	0.15252 (18)	0.41644 (13)	0.0410 (5)
C7	0.1881 (2)	0.41938 (17)	0.52853 (11)	0.0333 (4)
H7	0.1787	0.3976	0.5883	0.040*
C8	0.4229 (2)	0.70600 (17)	0.54632 (11)	0.0326 (4)
C9	0.4987 (2)	0.79022 (16)	0.61993 (10)	0.0293 (4)
C6	0.1079 (2)	0.33937 (16)	0.45849 (11)	0.0309 (4)
C10	0.4793 (2)	0.76888 (18)	0.71056 (11)	0.0391 (4)
H10	0.4198	0.6975	0.7298	0.047*
C13	0.5902 (2)	0.89769 (17)	0.59560 (11)	0.0356 (4)
H13	0.6063	0.9155	0.5357	0.043*
C11	0.5497 (2)	0.85525 (18)	0.77179 (12)	0.0412 (5)
H11	0.5345	0.8400	0.8321	0.049*
C12	0.6570 (2)	0.97802 (18)	0.66164 (12)	0.0409 (5)
H12	0.7188	1.0493	0.6442	0.049*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0732 (10)	0.0481 (8)	0.0244 (7)	−0.0064 (7)	0.0012 (6)	−0.0020 (6)
F1	0.0626 (8)	0.0443 (7)	0.0829 (9)	−0.0181 (6)	−0.0077 (7)	0.0013 (6)
N3	0.0503 (9)	0.0337 (9)	0.0330 (8)	−0.0030 (7)	−0.0008 (7)	−0.0037 (7)
C5	0.0396 (10)	0.0329 (10)	0.0321 (9)	0.0044 (8)	−0.0043 (7)	0.0006 (8)
N1	0.0396 (8)	0.0317 (8)	0.0294 (8)	0.0049 (7)	−0.0064 (6)	−0.0063 (6)
C3	0.0477 (11)	0.0413 (12)	0.0489 (12)	0.0054 (9)	−0.0140 (9)	−0.0165 (9)
O2	0.0734 (10)	0.0481 (8)	0.0329 (7)	−0.0127 (7)	−0.0087 (6)	0.0095 (6)
F2	0.1065 (11)	0.0841 (10)	0.0281 (6)	−0.0121 (8)	−0.0133 (6)	−0.0025 (6)
N2	0.0453 (8)	0.0313 (8)	0.0246 (7)	0.0009 (7)	−0.0064 (6)	−0.0036 (6)
C4	0.0536 (11)	0.0500 (12)	0.0275 (9)	0.0072 (10)	−0.0085 (8)	−0.0047 (8)
C1	0.0398 (10)	0.0348 (10)	0.0358 (10)	0.0047 (8)	−0.0005 (7)	0.0008 (8)
C2	0.0377 (10)	0.0328 (10)	0.0522 (12)	0.0006 (8)	−0.0032 (8)	−0.0023 (8)
C7	0.0382 (9)	0.0341 (10)	0.0273 (9)	0.0064 (8)	−0.0035 (7)	−0.0014 (7)
C8	0.0385 (9)	0.0335 (10)	0.0258 (9)	0.0068 (8)	0.0004 (7)	−0.0014 (7)
C9	0.0336 (9)	0.0275 (9)	0.0268 (8)	0.0060 (7)	0.0000 (7)	−0.0018 (7)
C6	0.0336 (9)	0.0288 (9)	0.0299 (9)	0.0079 (7)	−0.0032 (7)	−0.0022 (7)
C10	0.0524 (11)	0.0352 (10)	0.0298 (9)	−0.0094 (9)	0.0026 (8)	0.0018 (8)
C13	0.0447 (10)	0.0358 (10)	0.0266 (9)	0.0015 (8)	0.0037 (7)	0.0025 (8)
C11	0.0579 (12)	0.0418 (11)	0.0237 (9)	−0.0074 (9)	0.0012 (8)	−0.0003 (8)
C12	0.0504 (11)	0.0328 (10)	0.0397 (10)	−0.0066 (9)	0.0025 (8)	0.0023 (8)

Geometric parameters (Å, º) top

O1—C8	1.225 (2)	N2—H2B	0.8600
F1—C2	1.366 (2)	C1—C2	1.373 (3)
N3—C11	1.339 (2)	C1—C6	1.405 (3)
N3—C12	1.344 (2)	C1—H1	0.9300
C5—O2	1.358 (2)	C7—C6	1.464 (2)
C5—C4	1.396 (3)	C7—H7	0.9300
C5—C6	1.415 (2)	C8—C9	1.513 (2)
N1—C7	1.282 (2)	C9—C13	1.387 (2)
N1—N2	1.378 (2)	C9—C10	1.391 (2)
C3—C4	1.378 (3)	C10—C11	1.384 (3)
C3—C2	1.383 (3)	C10—H10	0.9300
C3—H2	0.9300	C13—C12	1.384 (3)
O2—H2A	0.8200	C13—H13	0.9300
F2—C4	1.363 (2)	C11—H11	0.9300
N2—C8	1.368 (2)	C12—H12	0.9300

C11—N3—C12	116.17 (16)	C6—C7—H7	120.3
O2—C5—C4	118.71 (16)	O1—C8—N2	122.51 (16)
O2—C5—C6	123.66 (16)	O1—C8—C9	121.27 (16)
C4—C5—C6	117.63 (17)	N2—C8—C9	116.22 (14)
C7—N1—N2	119.38 (14)	C13—C9—C10	117.64 (16)
C4—C3—C2	116.95 (17)	C13—C9—C8	118.00 (15)
C4—C3—H2	121.5	C10—C9—C8	124.33 (16)
C2—C3—H2	121.5	C1—C6—C5	119.45 (16)
C5—O2—H2A	109.5	C1—C6—C7	119.51 (15)
C8—N2—N1	116.89 (14)	C5—C6—C7	121.04 (16)
C8—N2—H2B	121.5	C11—C10—C9	119.15 (17)
N1—N2—H2B	121.6	C11—C10—H10	120.4
F2—C4—C3	118.94 (17)	C9—C10—H10	120.4
F2—C4—C5	117.48 (18)	C12—C13—C9	119.08 (16)
C3—C4—C5	123.58 (17)	C12—C13—H13	120.5
C2—C1—C6	119.51 (17)	C9—C13—H13	120.5
C2—C1—H1	120.2	N3—C11—C10	123.93 (16)
C6—C1—H1	120.2	N3—C11—H11	118.0
F1—C2—C1	119.21 (18)	C10—C11—H11	118.0
F1—C2—C3	117.93 (17)	N3—C12—C13	124.03 (17)
C1—C2—C3	122.86 (18)	N3—C12—H12	118.0
N1—C7—C6	119.48 (15)	C13—C12—H12	118.0
N1—C7—H7	120.3

Acknowledgements

S. Mittapalli and D. Sravanakumar Perumalla thank the UGC for Fellowships. J. B. Nanubolu thanks CSIR-IICT, Hyderabad, for facilities. Dr Rajesh G. Gonnade (CSIR-NCL, Pune) is thanked for single-crystal X-ray analysis of Compound-A (Form III) and Compound-C (Form II) at high temperature. We thank the SERB Scheme on Multi-component Crystals (EMR/2015/002075) and the J. C. Bose Fellowship (SR/S2/JCB-06/2009) for funding.

Funding information

The following funding is acknowledged: JC Bose fellowship. Bose Centre for Advanced Study and Research in Natural Sciences, University of Dhaka (scholarship No. SR/S2/JCB-06/2009).

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IUCrJ

Volume 4| Part 6| November 2017| Pages 812-823

ISSN: 2052-2525

https://doi.org/10.1107/S2052252517014658

CHEMISTRY | CRYSTENG

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research papers\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Thermomechanical effect in molecular crystals: the role of halogen-bonding interactions

1. Introduction

2. Experimental

2.1. Compound-A

2.2. Compound-B

2.3. Compound-C

2.4. Compound-D

2.5. Compound-E

2.6. X-ray crystallography

2.7. Powder X-ray diffraction (PXRD)

2.8. Infrared spectroscopy (IR)

2.9. Differential scanning calorimetry (DSC)

2.10. Thermogravimetric analysis (TGA)

2.11. Hot-stage microscopy (HSM)

2.12. Computations

3. Results and discussion

3.1. X-ray crystal structures

3.2. VT-PXRD and thermal analysis

3.3. Powder X-ray analysis

3.4. Thermomechanical effect and role of halogen bonding

3.5. Photochromism

4. Conclusions

Supporting information

Acknowledgements

Funding information

References

research papers