research communications
Syntheses and crystal structures of bis(4-methylpyridine-κN)bis(selenocyanato-κN)zinc(II) and catena-poly[[bis(4-methylpyridine-κN)cadmium(II)]-di-μ-selenocyanato-κ2N:Se;κ2Se:N]
aInstitut für Anorganische Chemie, Universität Kiel, Max-Eyth Str. 2, 24118 Kiel, Germany
*Correspondence e-mail: cnaether@ac.uni-kiel.de
The reactions of Zn(NO3)2.6H2O and Cd(NO3)2.4H2O with KSeCN and 4-methylpyridine (C6H7N; 4-picoline) lead to the formation of crystals of bis(4-methylpyridine-κN)bis(selenocyanato-κN)zinc(II), [Cd(NCSe)2(C6H7N)2] (1), and catena-poly[[bis(4-methylpyridine-κN)cadmium(II)]-di-μ-selenocyanato-κ2N:Se;κ2Se:N], [Cd(NCSe)2(C6H7N)2]n (2), suitable for single-crystal X-ray diffraction. The of compound 1 consists of one Zn cation that is located on a twofold rotation axis as well as one selenocyanate anion and one 4-methylpyridine ligand in general positions. The Zn cations are tetrahedrally coordinated by two terminal N-bonding thiocyanate anions and two 4-methylpyridine ligands, forming discrete complexes. The of compound 2 consists of two crystallographically independent Cd cations, of which one is located on a twofold rotation axis and the second on a center of inversion, as well as two crystallographically independent selenocyanate anions and two crystallographically independent 4-methylpyridine ligands in general positions. The Cd cations are octahedrally coordinated by two N- and two S-bonding selenocyanate anions and two 4-methylpyridine ligands and are linked into chains by pairs of selenocyanate anions. Within the chains, the Cd cations show an alternating cis–cis–trans and all-trans coordination and therefore, the chains are corrugated. PXRD investigations prove that the Zn compound was obtained as a pure phase and that the Cd compound contains a very small amount of an additional and unknown phase. In the IR spectrum of 1, the CN stretching vibration of the selenocyanate anion is observed at 2072 cm−1, whereas in the 2 it is shifted to 2094 cm−1, in agreement with the crystal structures.
Keywords: synthesis; crystal structure; Zn(NCSe)2; Cd(NCSe)2; coordination compounds; 4-methylpyridine.
1. Chemical context
Thio- and selenocyanate anions are versatile ligands because of their variable coordination modes (Buckingham, 1994; Barnett et al., 2002; Werner et al., 2015a). The most common mode is the terminal coordination and μ-1,3-bridging mode, where the latter is more pronounced for chalcophilic metal cations, whereas the former dominates for less chalcophilic metal cations. For a given metal thio- or selenocyanate and a given mono-coordinating coligand, usually several compounds with a different ratio between the metal cation and the coligand are observed, for example M(NCX)2(L)4 and M(NCX)2(L)2, or in very few cases also M(NCX)2(L) (M = +2 charge transition-metal cation, X = S, Se and L = neutral mono coordinating coligand). For compounds with the composition M(NCX)2(L)4 and octahedrally coordinated metal cations mostly discrete complexes are observed and hundreds of them are reported in the literature. For ligand-deficient compounds with the composition M(NCS)2(L)2, the octahedral coordination still dominates, but some metal ions such as Co2+ can show both octahedral and tetrahedral coordination (Mautner et al., 2018), whereas for ZnII, the tetrahedral coordination is found exclusively.
For simple geometrical considerations, compounds with the composition M(NCX)2(L)2 and cations that shows an octahedral coordination must contain μ-1,3-bridging thio or selenocyanate anions, and in this case the structural variability is much larger. In practically all cases they consist of M(NCX)2 chains or layers, but compared to chain compounds, layered structures are rare. In most of the layered compounds, the transition-metal cations are linked by single μ-1,3-bridging anionic ligands into layers (Werner et al., 2015b) or two metal cations are connected via pairs of anionic ligands into dinuclear units that condense into layers via single μ-1,3-bridging anions (Suckert et al., 2016). Moreover, for an octahedral coordination, in principle five different isomers exist, including the all-trans, the all-cis and three cis–cis–trans coordinations. The majority of chain compounds show an all-trans coordination in which the metal cations are linked by pairs of anionic ligands, leading to the formation of linear chains (Banerjee et al., 2005; Mautner et al., 2018; Werner et al., 2014; Rams et al., 2020). Linear chains are also observed in compounds where the coligands are still in the trans-position, whereas the thiocyanate N and S atoms are in the cis-position (Rams et al., 2017; Jochim et al., 2018), but there are very few examples where the coligands are in the cis-position, leading to the formation of corrugated chains (Banerjee et al., 2005; Shi, Chen & Liu, 2006; Makhlouf et al., 2022; Böhme et al., 2020). Corrugated chains are also observed for an all-cis coordination, but only very few examples have been reported (Shi, Sun et al., 2006; Zhang et al., 2006; Marsh, 2009). However, all of the structure types mentioned above are well known for thiocyanate coordination compounds, whereas the structures of selenocyanate compounds are not as well explored and it has not been thoroughly investigated whether compounds with thio- or selenocyanate anions and the same metal:coligand ratio always show the same structures and are, for example, isotypic. This might partly be traced back to the fact that some of the selenocyanate compounds are not very stable and that compounds with bridging anionic ligands are more difficult to prepare if less chalcophilic metal cations are used (Wriedt & Näther, 2010).
To investigate this in more detail, we prepared compounds based on Zn(NCSe)2 and Cd(NCSe)2, where the former metal ion prefers a tetrahedral and the latter an octahedral coordination. CdII is also very chalcophilic, which means that compounds with bridging anionic ligands can easily be prepared. 4-Methylpyridine (C6H7N) was selected as coligand, for which the corresponding thiocyanate compounds have been reported, whereas compounds with selenocyanate are unknown.
With Zn(NCS)2, compounds include three discrete complexes with the composition Zn(NCS)2(4-methylpyridine)4, in which the Zn cations are octahedrally coordinated by two terminal N-bonded thiocyanate anions and four 4-methylpyridine ligands [Cambridge Structural Database (Groom et al., 2016) refcodes EFESOX and YORHAO (Lipkowski et al., 1994) as well as QQQBUD (Ratho & Patel, 1969)]. Two of them (EFESOX and YORHAO) represent with additional 4-methylpyridine molecules or 4-methylpyridine and water molecules. There is also one 4-methylpyridine-deficient compound with the composition Zn(NCS)2(4-methylpyridine)2, in which the Zn cations are tetrahedrally coordinated by two terminal N-bonded thiocyanate anions and two 4-methylpyridine ligands (refcode VONTEX; Lipkowski, 1990).
With Cd(NCS)2, a solvate with the composition Cd(NCS)2(4-methylpyridine)4·4-methylpyridine·water has been reported, in which the Cd cations are octahedrally coordinated by two terminal N-bonded selenocyanate anions and four 4-methylpyridine ligands [refcodes DEXYIO (Dyadin et al., 1984), DEXYIO10, (Pervukhina et al., 1986) and DEXYIO11 (Marsh, 1995)]. More importantly, two compounds with the composition Cd(NCS)2(4-methylpyridine)2 are found that represent isomers. In one of these, the Cd cations are octahedrally coordinated by two terminal N- and S-bonded selenocyanate anions and two 4-methylpyridine ligands in an all-trans coordination. The Cd cations are linked by pairs of selenocyanate anions into chains, which because of the all-trans coordination are linear (FAPCOO02; Neumann et al., 2020). The second isomer was first reported in the triclinic P (FAPCOO; Taniguchi et al., 1986) but it was later pointed out that it is better described as monoclinic, in C2/c (FAPCOO01; Marsh, 1995). In this compound, the Cd cations are also octahedrally coordinated, linked into chains, but they are corrugated because an alternating all-trans and cis–cis–trans coordination is observed. The thermodynamic relations were determined for both isomers, indicating that they are related by monotropism with the isomer with corrugated chains as the thermodynamically stable phase (Neumann et al., 2020). Finally there is one 4-methylpyridine-deficient compound with the composition Cd(NCS)2(4-methylpyridine), in which the Cd cations are linked by pairs of anionic ligands into chains and each two of these chains are condensed into double chains via μ-1,1,3-(S,N,N)-bridging thiocyanate anions (refcode VUCBUT; Neumann et al., 2020).
To search for new compounds related to those noted above, Zn(NO3)2·6H2O and Cd(NO3)2·4H2O were reacted with KSeCN and 4-methylpyridine (4-picoline)2, which led to the formation of two compounds with the composition Zn(NCSe)2(4-methylpyridine)2 (1) and Cd(NCeS)2(4-methylpyridine)2 (2). IR spectroscopic investigations revealed that the CN stretching vibration is located at 2072 cm−1 for 1 and at 2094 cm−1 for 2, indicating that compound 1 contains terminally coordinated anionic ligands, whereas in 2 this value is at the borderline between that expected for a terminal and a bridging coordination (Figs. S1 and S2 in the supporting information). For both compounds, single crystals were obtained and characterized by single-crystal X-ray diffraction. Based on the crystallographic data, PXRD patterns were calculated and compared with the experimental pattern, showing that compound 1 was obtained as a pure phase, whereas compound 2 is contaminated with a very small amount of an unknown phase (Figs. S3 and S4). It is noted that even if Cd(NO3)2·4H2O and KSeCN are used in excess in the synthesis, there are no hints of the formation of a 4-methylpyridine-deficient compound with the composition Cd(NCSe)2(4-methylpyridine), as observed with Cd(NCS)2 (Neumann et al., 2020).
2. Structural commentary
The 1 consists of one selenocyanate anion and one 4-methylpyridine ligand in general positions, as well as one ZnII cation that is located on a twofold rotation axis (Fig. 1). The Zn cations are tetrahedrally coordinated by two symmetry-related terminal N-bonded selenocyanate anions and two symmetry-related 4-methylpyridine ligands (Fig. 1). The tetrahedra are slightly distorted with the Ns—Zn—Ns (s = selenocyanate) angle as the largest (Table 1). It is noted that compound 1 is isotypic to Zn(NCS)2(4-methylpyridine)2 reported by Lipkowski (1990).
of compound
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The 2 consists of two crystallographically independent Cd cations, of which Cd1 is located on a twofold rotation axis whereas Cd2 is located on a center of inversion, as well as two crystallographically independent selenocyanate anions and two crystallographically independent 4-methylpyridine ligands (Fig. 2). Both Cd cations are octahedrally coordinated by two N- and two S-bonding selenocyanate anions and two 4-methylpyridine ligands but Cd1 is in a cis–cis–trans coordination with the pyridine N atoms of the 4-methylpyridine ligand in the cis position, whereas Cd2 is in an all-trans coordination (Fig. 2). Both octahedra are slightly distorted but Cd1 is more distorted than Cd2 (Table 2). The Cd cations are linked by pairs of selenocyanate anions into chains that show an alternating cis–cis–trans and all-trans coordination. Because of the former, these chains are corrugated (Fig. 3).
of compoundCompound 2 is isotypic to the second isomer of Cd(NCS)2(4-methylpyridine)2 that crystallizes in the monoclinic C2/c (Marsh, 1995). In this context, it is noted that two modifications are also known for the corresponding Fe compound Fe(NCS)2(4-methylpyridine)2 (Neumann et al., 2020), of which form I is isotypic to compound 2 and the corrugated chain isomer of Cd(NCS)2(4-methylpyridine)2, whereas form II of the Fe compound is isotypic to the linear chain isomer. For the Fe isomers, the same thermodynamic relations were found as for the isomers with Cd(NCS)2 with the corrugated chain isomer as the thermodynamically stable form (Neumann et al., 2020). Moreover, compound 2 is also isotypic to Cd(NCS)2(4-chloropyridine)2 reported by Goher et al. (2003; refcode EMASIU). This can be traced back to the fact that the van der Waals radii of a methyl group and a chlorine atom are comparable, which is expressed by the so-called chloro–methyl exchange rule (Desiraju & Sarma, 1986 and references cited therein).
Finally, it is noted that some compounds with the general composition Cd(NCSe)2(L)2 with L as a monocoordinating coligand are reported, in which the Cd cations are linked by pairs of anionic ligands into chains, but the majority of compounds show an all-trans coordination and the formation of linear chains. An overview is given in the database survey.
3. Supramolecular features
In the 1, the discrete complexes are arranged into columns that propagate along the c-axis direction (Fig. 4). Within these columns, the selenocyanate anions and the 4-methylpyridine ligands always point in the same direction, from which the non-centrosymmetric arrangement is visible (Fig. 4). There are no directional intermolecular interactions between the complexes and nor is there any indication of π–π interactions.
of compoundIn compound 2, the chains are closely packed and propagate along the [101] direction (Fig. 5). As in compound 1, no pronounced intermolecular interactions are observed.
4. Database survey
According to a search in the Cambridge Structural Database (CSD Version 5.43, March 2022; Groom et al., 2016), no selenocyanate coordination compounds with 4-methylpyridine as anionic ligand have been reported but many compounds with the thiocyanate as anion can be found. Those with Zn(NCS)2 and Cd(NCS)2 were already mentioned in the Chemical context section (see above).
It is also noted that several Cd(NCSe)2 chain compounds are reported in the CSD, but in all of them the Cd cations show an all-trans coordination and are linked into linear chains [BIWTOR (Fettouhi et al., 2008), DAYWAE (Sadhu et al., 2017), DOJBEK (Choudhury et al., 2008), FAPGAG (Jess et al., 2012), FIMJIW (Werner et al., 2013), NAQXIO (Boeckmann, Jess et al., 2011), OLOZAQ (Li & Liu, 2003), OWOHOY (Boeckmann, Reinert & Näther, 2011), QIPYAP (Secondo et al., 2000) and ZANQAI (Werner et al., 2012)].
However, in this context it is noted that some selenocyanate compounds with pyridine as coligand are found, of which those with the composition M(NCSe)2(pyridine)2 (M = Zn, Co, Ni, Cd) are of the most interest. The Zn compound crystallizes as discrete complexes with a tetrahedral coordination (OWOJEQ; Boeckmann, Reinert & Näther, 2011), wheres the compounds with FeII, CoII and CdII crystallize as linear chains with an all-trans coordination [CAQVIB (Boeckmann et al., 2012), ITISUA (Boeckmann & Näther, 2011)].
5. Synthesis and crystallization
Synthesis
Zn(NO3)2·6H2O and Cd(NO3)2·4H2O were purchased from Sigma Aldrich and KSeCN was purchased from Alfa Aesar. All chemicals were used without any further purification.
Synthesis of compound 1.
0.5 mmol (143 mg) of Zn(NO3)2·6H2O and 1 mmol (144 mg) of KSeCN were reacted with 1 mmol (97.2 µl) of 4-methylpyridine in 2 ml of ethanol. The reaction mixture was stirred for 2 d and the colorless precipitate was filtered off, washed with a very small amount of ethanol and dried at room temperature. Single crystals were obtained from the filtrate by slow evaporation of the solvent.
Synthesis of compound 2.
0.5 mmol (154 mg) of Cd(NO3)2·4H2O and 1 mmol (144 mg) of KSeCN were reacted with 1 mmol (97.2 µl) of 4-methylpyridine in 2 ml of ethanol. The reaction mixture was stirred for 2 d and the colorless precipitate was filtered off, washed with a very small amount of ethanol and dried at room temperature. Single crystals were obtained from the filtrate by slow evaporation of the solvent.
Experimental details
The XRPD measurements were performed with a Stoe Transmission Powder Diffraction System (STADI P) equipped with a MYTHEN 1K detector and a Johansson-type Ge(111) monochromator using Cu Kα1 radiation (λ = 1.540598 Å).
The IR spectra were measured using an ATI Mattson Genesis Series FTIR Spectrometer, control software: WINFIRST, from ATI Mattson.
Thermogravimetry and differential thermoanalysis (TG–DTA) measurements were performed in a dynamic nitrogen atmosphere in Al2O3 crucibles using a STA–PT 1000 thermobalance from Linseis. The instrument was calibrated using standard reference materials.
6. Refinement
Crystal data, data collection and structure . C-bound H atoms were positioned with idealized geometry (C—H = 0.93–0.96 Å; methyl H atoms allowed to rotate but not to tip) and were refined isotropically with Uiso(H) = 1.2Ueq(C) (1.5 for methyl H atoms) using a riding model.
details are summarized in Table 3
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Supporting information
https://doi.org/10.1107/S2056989023000920/hb8052sup1.cif
contains datablocks I, II, global. DOI:Fig. S1. IR spectrum of compound 1. Given is the value of the CN stretching vibration of the selenocyanate anions. DOI: https://doi.org/10.1107/S2056989023000920/hb8052sup4.jpg
Fig. S2. IR spectrum of compound 2. Given is the value of the CN stretching vibration of the selenocyanate anions. DOI: https://doi.org/10.1107/S2056989023000920/hb8052sup5.jpg
Fig. S3. Experimental (top) and calculated PXRD pattern (bottom) of compound 1. DOI: https://doi.org/10.1107/S2056989023000920/hb8052sup6.jpg
Fig. S4. Experimental (top) and calculated PXRD pattern (bottom) of compound 2. DOI: https://doi.org/10.1107/S2056989023000920/hb8052sup7.jpg
Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989023000920/hb8052Isup8.hkl
Structure factors: contains datablock II. DOI: https://doi.org/10.1107/S2056989023000920/hb8052IIsup9.hkl
For both structures, data collection: X-AREA (Stoe, 2008); cell
X-AREA (Stoe, 2008); data reduction: X-AREA (Stoe, 2008); program(s) used to solve structure: SHELXT2014/5 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2016/6 (Sheldrick, 2015b); molecular graphics: DIAMOND (Brandenburg & Putz, 1999); software used to prepare material for publication: publCIF (Westrip, 2010).[Zn(NCSe)2(C6H7N)2] | Dx = 1.734 Mg m−3 |
Mr = 461.58 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, Fdd2 | Cell parameters from 14188 reflections |
a = 37.3964 (18) Å | θ = 2.2–27.5° |
b = 18.4780 (7) Å | µ = 5.51 mm−1 |
c = 5.1164 (2) Å | T = 293 K |
V = 3535.5 (3) Å3 | Block, colorless |
Z = 8 | 0.25 × 0.20 × 0.20 mm |
F(000) = 1792 |
STOE IPDS-2 diffractometer | 1823 reflections with I > 2σ(I) |
ω scans | Rint = 0.027 |
Absorption correction: numerical (X-Red and X-Shape; Stoe, 2008) | θmax = 27.5°, θmin = 2.2° |
Tmin = 0.305, Tmax = 0.547 | h = −48→48 |
14188 measured reflections | k = −23→23 |
1953 independent reflections | l = −6→5 |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.029 | w = 1/[σ2(Fo2) + (0.0306P)2 + 2.9003P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.067 | (Δ/σ)max < 0.001 |
S = 1.13 | Δρmax = 0.26 e Å−3 |
1953 reflections | Δρmin = −0.22 e Å−3 |
97 parameters | Absolute structure: Flack x determined using 675 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
1 restraint | Absolute structure parameter: 0.012 (8) |
Primary atom site location: dual |
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. |
x | y | z | Uiso*/Ueq | ||
Zn1 | 0.000000 | 0.500000 | 0.44116 (13) | 0.05955 (17) | |
Se1 | 0.05719 (2) | 0.30585 (3) | 0.91932 (12) | 0.1023 (2) | |
N11 | 0.03820 (7) | 0.54594 (16) | 0.2162 (7) | 0.0548 (7) | |
C11 | 0.03560 (12) | 0.6142 (2) | 0.1324 (10) | 0.0702 (12) | |
H11 | 0.016846 | 0.642476 | 0.193939 | 0.084* | |
C1 | 0.03662 (12) | 0.3754 (3) | 0.7402 (9) | 0.0681 (11) | |
N1 | 0.02308 (11) | 0.4217 (2) | 0.6310 (9) | 0.0806 (11) | |
C15 | 0.06600 (11) | 0.5073 (2) | 0.1294 (9) | 0.0651 (10) | |
H15 | 0.068456 | 0.459745 | 0.185725 | 0.078* | |
C12 | 0.05934 (12) | 0.6443 (2) | −0.0402 (10) | 0.0748 (12) | |
H12 | 0.056342 | 0.691924 | −0.095090 | 0.090* | |
C16 | 0.11412 (15) | 0.6356 (4) | −0.3232 (15) | 0.0985 (16) | |
H16A | 0.115697 | 0.686987 | −0.298495 | 0.148* | |
H16B | 0.106438 | 0.625496 | −0.498454 | 0.148* | |
H16C | 0.137157 | 0.614117 | −0.294057 | 0.148* | |
C14 | 0.09088 (11) | 0.5347 (2) | −0.0380 (11) | 0.0734 (11) | |
H14 | 0.110202 | 0.506325 | −0.089267 | 0.088* | |
C13 | 0.08745 (11) | 0.6043 (3) | −0.1317 (9) | 0.0670 (11) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Zn1 | 0.0556 (3) | 0.0672 (3) | 0.0558 (3) | −0.0044 (3) | 0.000 | 0.000 |
Se1 | 0.1184 (4) | 0.0790 (3) | 0.1095 (5) | 0.0235 (3) | −0.0162 (4) | 0.0132 (4) |
N11 | 0.0497 (14) | 0.0573 (16) | 0.0573 (19) | −0.0027 (12) | −0.0047 (14) | 0.0011 (15) |
C11 | 0.065 (2) | 0.064 (2) | 0.081 (3) | 0.0077 (18) | 0.007 (2) | 0.006 (2) |
C1 | 0.069 (2) | 0.073 (3) | 0.063 (3) | −0.007 (2) | −0.002 (2) | 0.002 (2) |
N1 | 0.081 (2) | 0.088 (3) | 0.073 (3) | 0.002 (2) | −0.007 (2) | 0.017 (2) |
C15 | 0.063 (2) | 0.0566 (19) | 0.076 (3) | 0.0029 (16) | 0.0013 (19) | −0.001 (2) |
C12 | 0.080 (3) | 0.069 (2) | 0.075 (3) | −0.001 (2) | 0.008 (3) | 0.013 (2) |
C16 | 0.090 (3) | 0.120 (4) | 0.085 (3) | −0.019 (3) | 0.021 (3) | 0.015 (4) |
C14 | 0.063 (2) | 0.076 (3) | 0.081 (3) | 0.0048 (18) | 0.011 (2) | −0.007 (3) |
C13 | 0.064 (2) | 0.079 (3) | 0.057 (3) | −0.014 (2) | 0.0001 (18) | −0.0001 (19) |
Zn1—N1 | 1.945 (4) | C15—C14 | 1.362 (7) |
Zn1—N1i | 1.945 (4) | C15—H15 | 0.9300 |
Zn1—N11i | 2.021 (3) | C12—C13 | 1.368 (6) |
Zn1—N11 | 2.021 (3) | C12—H12 | 0.9300 |
Se1—C1 | 1.756 (5) | C16—C13 | 1.513 (7) |
N11—C11 | 1.335 (5) | C16—H16A | 0.9600 |
N11—C15 | 1.337 (5) | C16—H16B | 0.9600 |
C11—C12 | 1.371 (6) | C16—H16C | 0.9600 |
C11—H11 | 0.9300 | C14—C13 | 1.379 (6) |
C1—N1 | 1.140 (5) | C14—H14 | 0.9300 |
N1—Zn1—N1i | 120.0 (3) | C14—C15—H15 | 118.6 |
N1—Zn1—N11i | 106.61 (15) | C13—C12—C11 | 119.9 (4) |
N1i—Zn1—N11i | 106.44 (15) | C13—C12—H12 | 120.1 |
N1—Zn1—N11 | 106.45 (15) | C11—C12—H12 | 120.1 |
N1i—Zn1—N11 | 106.61 (15) | C13—C16—H16A | 109.5 |
N11i—Zn1—N11 | 110.59 (18) | C13—C16—H16B | 109.5 |
C11—N11—C15 | 117.0 (4) | H16A—C16—H16B | 109.5 |
C11—N11—Zn1 | 121.9 (3) | C13—C16—H16C | 109.5 |
C15—N11—Zn1 | 121.0 (3) | H16A—C16—H16C | 109.5 |
N11—C11—C12 | 122.9 (4) | H16B—C16—H16C | 109.5 |
N11—C11—H11 | 118.5 | C15—C14—C13 | 120.1 (4) |
C12—C11—H11 | 118.5 | C15—C14—H14 | 120.0 |
N1—C1—Se1 | 177.9 (4) | C13—C14—H14 | 120.0 |
C1—N1—Zn1 | 179.3 (4) | C12—C13—C14 | 117.2 (4) |
N11—C15—C14 | 122.9 (4) | C12—C13—C16 | 121.4 (4) |
N11—C15—H15 | 118.6 | C14—C13—C16 | 121.3 (5) |
Symmetry code: (i) −x, −y+1, z. |
[Cd(NCSe)2(C6H7N)2] | F(000) = 1936 |
Mr = 508.61 | Dx = 1.902 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
a = 20.7296 (11) Å | Cell parameters from 17056 reflections |
b = 9.4896 (3) Å | θ = 2.2–26.0° |
c = 19.7364 (10) Å | µ = 5.33 mm−1 |
β = 113.794 (3)° | T = 293 K |
V = 3552.5 (3) Å3 | Block, colorless |
Z = 8 | 0.18 × 0.14 × 0.10 mm |
STOE IPDS-2 diffractometer | 2911 reflections with I > 2σ(I) |
ω scans | Rint = 0.038 |
Absorption correction: numerical (X-Red and X-Shape; Stoe, 2008) | θmax = 26.0°, θmin = 2.2° |
Tmin = 0.321, Tmax = 0.446 | h = −25→25 |
17056 measured reflections | k = −8→11 |
3469 independent reflections | l = −24→24 |
Refinement on F2 | Primary atom site location: dual |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.039 | H-atom parameters constrained |
wR(F2) = 0.076 | w = 1/[σ2(Fo2) + (0.0229P)2 + 7.6388P] where P = (Fo2 + 2Fc2)/3 |
S = 1.13 | (Δ/σ)max = 0.001 |
3469 reflections | Δρmax = 0.74 e Å−3 |
194 parameters | Δρmin = −0.63 e Å−3 |
0 restraints |
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. |
x | y | z | Uiso*/Ueq | ||
Cd1 | 0.500000 | 0.47303 (5) | 0.250000 | 0.05827 (14) | |
Cd2 | 0.750000 | 0.250000 | 0.500000 | 0.05746 (13) | |
N1 | 0.5569 (2) | 0.4762 (5) | 0.37921 (19) | 0.0724 (11) | |
C1 | 0.5986 (2) | 0.4628 (4) | 0.4381 (2) | 0.0539 (10) | |
Se1 | 0.66318 (2) | 0.44348 (6) | 0.53116 (2) | 0.06746 (15) | |
N2 | 0.6944 (2) | 0.2763 (5) | 0.3720 (2) | 0.0715 (11) | |
C2 | 0.6512 (2) | 0.2729 (5) | 0.3135 (2) | 0.0582 (10) | |
Se2 | 0.58388 (3) | 0.26863 (6) | 0.22157 (3) | 0.07812 (18) | |
N11 | 0.57906 (18) | 0.6528 (4) | 0.2507 (2) | 0.0640 (9) | |
C11 | 0.6021 (2) | 0.6648 (5) | 0.1971 (2) | 0.0700 (12) | |
H11 | 0.585089 | 0.601802 | 0.157671 | 0.084* | |
C12 | 0.6496 (3) | 0.7651 (5) | 0.1968 (3) | 0.0679 (12) | |
H12 | 0.663234 | 0.769834 | 0.157369 | 0.081* | |
C13 | 0.6773 (2) | 0.8592 (5) | 0.2548 (3) | 0.0629 (11) | |
C14 | 0.6536 (3) | 0.8466 (6) | 0.3102 (3) | 0.0938 (18) | |
H14 | 0.670037 | 0.907735 | 0.350437 | 0.113* | |
C15 | 0.6059 (3) | 0.7438 (6) | 0.3062 (3) | 0.0909 (18) | |
H15 | 0.591248 | 0.737234 | 0.344883 | 0.109* | |
C16 | 0.7307 (3) | 0.9687 (6) | 0.2579 (3) | 0.0824 (15) | |
H16A | 0.776309 | 0.925625 | 0.273302 | 0.124* | |
H16B | 0.732202 | 1.040818 | 0.292621 | 0.124* | |
H16C | 0.717741 | 1.009812 | 0.209722 | 0.124* | |
N21 | 0.67039 (19) | 0.0657 (4) | 0.4930 (2) | 0.0641 (9) | |
C21 | 0.6897 (3) | −0.0359 (6) | 0.5440 (3) | 0.0803 (15) | |
H21 | 0.736013 | −0.036657 | 0.578951 | 0.096* | |
C22 | 0.6451 (3) | −0.1392 (6) | 0.5477 (3) | 0.0844 (15) | |
H22 | 0.661708 | −0.207526 | 0.584525 | 0.101* | |
C23 | 0.5759 (3) | −0.1424 (5) | 0.4974 (3) | 0.0708 (13) | |
C24 | 0.5563 (3) | −0.0392 (6) | 0.4441 (3) | 0.0744 (13) | |
H24 | 0.510543 | −0.037549 | 0.407877 | 0.089* | |
C25 | 0.6039 (3) | 0.0619 (6) | 0.4438 (3) | 0.0736 (13) | |
H25 | 0.588663 | 0.130929 | 0.407229 | 0.088* | |
C26 | 0.5257 (3) | −0.2518 (6) | 0.5017 (4) | 0.0890 (17) | |
H26A | 0.479146 | −0.212412 | 0.484738 | 0.133* | |
H26B | 0.540300 | −0.282538 | 0.552103 | 0.133* | |
H26C | 0.525360 | −0.330752 | 0.471169 | 0.133* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cd1 | 0.0473 (2) | 0.0720 (3) | 0.0452 (2) | 0.000 | 0.00794 (18) | 0.000 |
Cd2 | 0.0497 (2) | 0.0680 (3) | 0.0476 (2) | 0.0026 (2) | 0.01232 (19) | 0.00515 (19) |
N1 | 0.061 (2) | 0.095 (3) | 0.045 (2) | 0.012 (2) | 0.0049 (17) | −0.0056 (19) |
C1 | 0.051 (2) | 0.058 (3) | 0.052 (2) | 0.0048 (18) | 0.021 (2) | −0.0023 (18) |
Se1 | 0.0620 (3) | 0.0856 (4) | 0.0431 (2) | 0.0160 (2) | 0.0091 (2) | −0.0016 (2) |
N2 | 0.068 (2) | 0.097 (3) | 0.044 (2) | 0.018 (2) | 0.0162 (18) | 0.0062 (19) |
C2 | 0.062 (3) | 0.059 (3) | 0.055 (2) | 0.008 (2) | 0.025 (2) | 0.0001 (19) |
Se2 | 0.0686 (3) | 0.0937 (4) | 0.0547 (3) | 0.0124 (3) | 0.0068 (2) | −0.0188 (2) |
N11 | 0.056 (2) | 0.078 (3) | 0.059 (2) | −0.0090 (19) | 0.0253 (17) | −0.0172 (19) |
C11 | 0.070 (3) | 0.083 (3) | 0.056 (2) | −0.013 (3) | 0.024 (2) | −0.019 (2) |
C12 | 0.071 (3) | 0.077 (3) | 0.061 (3) | −0.003 (2) | 0.033 (2) | −0.010 (2) |
C13 | 0.054 (2) | 0.065 (3) | 0.070 (3) | −0.001 (2) | 0.025 (2) | −0.012 (2) |
C14 | 0.113 (4) | 0.100 (4) | 0.084 (4) | −0.043 (4) | 0.057 (3) | −0.045 (3) |
C15 | 0.110 (4) | 0.102 (4) | 0.084 (4) | −0.035 (4) | 0.063 (3) | −0.039 (3) |
C16 | 0.077 (3) | 0.081 (4) | 0.096 (4) | −0.012 (3) | 0.042 (3) | −0.018 (3) |
N21 | 0.061 (2) | 0.069 (2) | 0.062 (2) | 0.0001 (19) | 0.0245 (18) | 0.0037 (19) |
C21 | 0.073 (3) | 0.079 (4) | 0.073 (3) | −0.007 (3) | 0.014 (3) | 0.007 (3) |
C22 | 0.088 (4) | 0.074 (3) | 0.082 (3) | −0.009 (3) | 0.025 (3) | 0.006 (3) |
C23 | 0.076 (3) | 0.064 (3) | 0.082 (3) | −0.006 (3) | 0.042 (3) | −0.019 (3) |
C24 | 0.054 (3) | 0.082 (4) | 0.083 (3) | −0.005 (2) | 0.023 (2) | −0.014 (3) |
C25 | 0.060 (3) | 0.082 (3) | 0.074 (3) | 0.004 (3) | 0.022 (2) | 0.003 (3) |
C26 | 0.089 (4) | 0.080 (4) | 0.114 (5) | −0.018 (3) | 0.058 (4) | −0.022 (3) |
Cd1—N1i | 2.338 (3) | C13—C14 | 1.373 (6) |
Cd1—N1 | 2.338 (3) | C13—C16 | 1.501 (7) |
Cd1—N11i | 2.362 (4) | C14—C15 | 1.370 (7) |
Cd1—N11 | 2.362 (4) | C14—H14 | 0.9300 |
Cd1—Se2 | 2.8085 (6) | C15—H15 | 0.9300 |
Cd1—Se2i | 2.8086 (6) | C16—H16A | 0.9600 |
Cd2—N2ii | 2.328 (4) | C16—H16B | 0.9600 |
Cd2—N2 | 2.328 (4) | C16—H16C | 0.9600 |
Cd2—N21ii | 2.370 (4) | N21—C25 | 1.329 (6) |
Cd2—N21 | 2.370 (4) | N21—C21 | 1.332 (6) |
Cd2—Se1ii | 2.8073 (5) | C21—C22 | 1.369 (7) |
Cd2—Se1 | 2.8073 (5) | C21—H21 | 0.9300 |
N1—C1 | 1.142 (5) | C22—C23 | 1.378 (7) |
C1—Se1 | 1.793 (4) | C22—H22 | 0.9300 |
N2—C2 | 1.141 (5) | C23—C24 | 1.373 (7) |
C2—Se2 | 1.788 (5) | C23—C26 | 1.497 (7) |
N11—C15 | 1.329 (6) | C24—C25 | 1.377 (7) |
N11—C11 | 1.329 (5) | C24—H24 | 0.9300 |
C11—C12 | 1.372 (6) | C25—H25 | 0.9300 |
C11—H11 | 0.9300 | C26—H26A | 0.9600 |
C12—C13 | 1.381 (6) | C26—H26B | 0.9600 |
C12—H12 | 0.9300 | C26—H26C | 0.9600 |
N1i—Cd1—N1 | 178.5 (2) | C11—C12—C13 | 120.3 (4) |
N1i—Cd1—N11i | 86.63 (14) | C11—C12—H12 | 119.8 |
N1—Cd1—N11i | 92.29 (13) | C13—C12—H12 | 119.8 |
N1i—Cd1—N11 | 92.30 (13) | C14—C13—C12 | 116.2 (4) |
N1—Cd1—N11 | 86.63 (14) | C14—C13—C16 | 121.5 (4) |
N11i—Cd1—N11 | 87.53 (18) | C12—C13—C16 | 122.3 (4) |
N1i—Cd1—Se2 | 82.62 (11) | C15—C14—C13 | 119.9 (5) |
N1—Cd1—Se2 | 98.42 (10) | C15—C14—H14 | 120.0 |
N11i—Cd1—Se2 | 169.06 (8) | C13—C14—H14 | 120.0 |
N11—Cd1—Se2 | 90.90 (9) | N11—C15—C14 | 124.2 (5) |
N1i—Cd1—Se2i | 98.42 (10) | N11—C15—H15 | 117.9 |
N1—Cd1—Se2i | 82.62 (11) | C14—C15—H15 | 117.9 |
N11i—Cd1—Se2i | 90.90 (9) | C13—C16—H16A | 109.5 |
N11—Cd1—Se2i | 169.06 (8) | C13—C16—H16B | 109.5 |
Se2—Cd1—Se2i | 92.64 (3) | H16A—C16—H16B | 109.5 |
N2ii—Cd2—N2 | 180.0 | C13—C16—H16C | 109.5 |
N2ii—Cd2—N21ii | 89.30 (14) | H16A—C16—H16C | 109.5 |
N2—Cd2—N21ii | 90.70 (14) | H16B—C16—H16C | 109.5 |
N2ii—Cd2—N21 | 90.70 (14) | C25—N21—C21 | 116.0 (4) |
N2—Cd2—N21 | 89.30 (14) | C25—N21—Cd2 | 123.7 (3) |
N21ii—Cd2—N21 | 180.0 | C21—N21—Cd2 | 120.0 (3) |
N2ii—Cd2—Se1ii | 95.00 (10) | N21—C21—C22 | 123.7 (5) |
N2—Cd2—Se1ii | 84.99 (10) | N21—C21—H21 | 118.1 |
N21ii—Cd2—Se1ii | 90.14 (9) | C22—C21—H21 | 118.1 |
N21—Cd2—Se1ii | 89.86 (9) | C21—C22—C23 | 120.4 (5) |
N2ii—Cd2—Se1 | 85.00 (10) | C21—C22—H22 | 119.8 |
N2—Cd2—Se1 | 95.01 (10) | C23—C22—H22 | 119.8 |
N21ii—Cd2—Se1 | 89.86 (9) | C24—C23—C22 | 115.8 (5) |
N21—Cd2—Se1 | 90.14 (9) | C24—C23—C26 | 122.8 (5) |
Se1ii—Cd2—Se1 | 180.000 (16) | C22—C23—C26 | 121.4 (5) |
C1—N1—Cd1 | 161.8 (4) | C23—C24—C25 | 120.7 (5) |
N1—C1—Se1 | 179.0 (4) | C23—C24—H24 | 119.7 |
C1—Se1—Cd2 | 97.03 (13) | C25—C24—H24 | 119.7 |
C2—N2—Cd2 | 159.7 (4) | N21—C25—C24 | 123.3 (5) |
N2—C2—Se2 | 179.5 (5) | N21—C25—H25 | 118.4 |
C2—Se2—Cd1 | 94.25 (14) | C24—C25—H25 | 118.4 |
C15—N11—C11 | 115.8 (4) | C23—C26—H26A | 109.5 |
C15—N11—Cd1 | 122.2 (3) | C23—C26—H26B | 109.5 |
C11—N11—Cd1 | 121.9 (3) | H26A—C26—H26B | 109.5 |
N11—C11—C12 | 123.5 (4) | C23—C26—H26C | 109.5 |
N11—C11—H11 | 118.3 | H26A—C26—H26C | 109.5 |
C12—C11—H11 | 118.3 | H26B—C26—H26C | 109.5 |
Symmetry codes: (i) −x+1, y, −z+1/2; (ii) −x+3/2, −y+1/2, −z+1. |
Acknowledgements
This work was supported by the state of Schleswig-Holstein.
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