4-Meth­oxy-2-{(E)-[(thio­phen-2-yl)methyl­imino]­meth­yl}phenol

Kantar, E.N.; Köysal, Y.; Macit, M.; Er, E.; Soylu, M.S.

doi:10.1107/S1600536812036586

organic compounds

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ISSN: 2056-9890

Volume 68| Part 9| September 2012| Page o2801

doi:10.1107/S1600536812036586

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4-Methoxy-2-{(E)-[(thiophen-2-yl)methylimino]methyl}phenol

Esen Nur Kantar,^a ^* Yavuz Köysal,^b Mustafa Macit,^c Ebru Er ^c and Mustafa Serkan Soylu ^d

^aDepartment of Physics, Faculty of Arts and Sciences, Ondokuz Mayıs University, TR-55139 Samsun, Turkey, ^bYesilyurt Demir Celik Vocational School, Ondokuz Mayıs University, TR-55139 Samsun, Turkey, ^cDepartment of Chemistry, Faculty of Arts and Sciences, Ondokuz Mayıs University, Kurupelit, 55139 Samsun, Turkey, and ^dDepartment of Physics, Faculty of Arts and Sciences, Giresun University, Giresun, Turkey
^*Correspondence e-mail: esen.nur@oposta.omu.edu.tr

(Received 19 July 2012; accepted 22 August 2012; online 31 August 2012)

The title Schiff base, C₁₃H₁₃NO₂S, adopts the phenol–imine tautomeric form and reveals an intramolecular O—H⋯N hydrogen bond involving the hydroxy group and the imino N atom, forming an S(6) ring. The molecule is highly twisted with respect to the central imine group, which is reflected in the dihedral angle of 67.83 (10)° formed by the thienyl and phenol rings. The crystal packing is characterized by weak C—H⋯O and C—H⋯π interactions.

Related literature

Schiff bases of salicylaldehyde may exhibit thermochromism or photochromism, depending on the planarity or non-planarity, respectively, of the molecule, see: Amimoto & Kawato (2005 ); Schmidt & Cohen (1964 ). For a related structure, see: Kantar et al. (2012 ). For hydrogen-bond motifs, see: Bernstein et al. (1995 )

Experimental

Crystal data

C₁₃H₁₃NO₂S
M_r = 247.30
Monoclinic, P 2₁
a = 5.6325 (3) Å
b = 8.1666 (3) Å
c = 13.4836 (6) Å
β = 96.798 (4)°
V = 615.86 (5) Å³
Z = 2
Mo Kα radiation
μ = 0.25 mm⁻¹
T = 293 K
0.20 × 0.15 × 0.10 mm

Data collection

Oxford Diffraction SuperNova (single source at offset) Eos diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2007 $[Oxford Diffraction (2007). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]$ ) T_min = 0.951, T_max = 0.975
2221 measured reflections
1809 independent reflections
1472 reflections with I > 2σ(I)
R_int = 0.015

Refinement

R[F² > 2σ(F²)] = 0.047
wR(F²) = 0.109
S = 1.06
1809 reflections
159 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.16 e Å⁻³
Δρ_min = −0.21 e Å⁻³
Absolute structure: Flack (1983 ), 640 Friedel pairs
Flack parameter: 0.04 (13)

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C1–C6 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N1	1.10 (6)	1.63 (7)	2.616 (4)	147 (5)
C8—H8A⋯O2ⁱ	0.97	2.77	3.592 (4)	143
C2—H2⋯Cg1ⁱⁱ	0.93	3.00	3.631 (4)	127
Symmetry codes: (i) $[-x, y-{\script{1\over 2}}, -z+1]$ ; (ii) $[-x+1, y+{\script{1\over 2}}, -z+1]$ .

Data collection: CrysAlis PRO (Oxford Diffraction, 2007 $[Oxford Diffraction (2007). CrysAlis PRO. Oxford Diffraction Ltd, Abingdon, England.]$ ); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812036586/zq2177sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812036586/zq2177Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812036586/zq2177Isup3.cml

checkCIF report

Comment top

The title Schiff base, C₁₃H₁₃NO₂S, adopts in the crystal structure the phenol-imine tautomeric form and reveals an intramolecular O—H···N hydrogen bond between the hydroxy O atom and the imino N atom (Kantar et al., 2012) generating a nearly planar six-membered ring, a S(6) ring motif according to Bernstein et al. (1995).

It is known that Schiff bases of salicylaldehyde may exhibit thermochromism or photochromism, depending on planarity or non-planarity of the molecule (Schmidt & Cohen, 1964; Amimoto & Kawato, 2005). The X-ray diffraction study of the title compound shows that the molecule is highly twisted with respect to the central imine group, which is reflected in the dihedral angle of 67.83 (10)° formed by the thienyl and phenol rings.

The crystal packing is characterized by weak C—H···O (see Table 1) and C—H···π interactions: the distance between C2—H2 and Cg1ⁱⁱ (C1-C6 ring) is 3.00 Å [symmetry code: ii = 1-x, 0.5+y, 1-z].

Related literature top

Schiff bases of salicylaldehyde may exhibit thermochromism or photochromism, depending on the planarity or non-planarity, respectively, of the molecule, see: Amimoto & Kawato (2005); Schmidt & Cohen (1964). For a related structure, see: Kantar et al. (2012). For hydrogen-bond motifs, see: Bernstein et al. (1995)

Experimental top

The title compound was prepared by refluxing a mixture of a solution containing 2-hydroxy-5-methoxybenzaldehyde (15.22 mg, 0.1 mmol) in ethanol (20 ml) and a solution containing 2-thiophenemethylamine (11.32 mg, 0.1 mmol) in ethanol (20 ml). The reaction mixture was stirred for 5 h under reflux. Single crystals of the title compound suitable for X-ray analysis were obtained by slow evaporation of the ethanol solution (yield 64%; m.p. 353–355 K).

Computing details top

Data collection: CrysAlis PRO (Oxford Diffraction, 2007); cell refinement: CrysAlis PRO (Oxford Diffraction, 2007); data reduction: CrysAlis PRO (Oxford Diffraction, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

A view of the title compound with the atom-numbering scheme and 50% probability displacement ellipsoids.

Packing diagram of the title compound along the a axis.

4-Methoxy-2-{(E)-[(thiophen-2-yl)methylimino]methyl}phenol top

Crystal data top

C₁₃H₁₃NO₂S	F(000) = 260
M_r = 247.30	D_x = 1.334 Mg m⁻³
Monoclinic, P2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2yb	Cell parameters from 958 reflections
a = 5.6325 (3) Å	θ = 3.6–28.7°
b = 8.1666 (3) Å	µ = 0.25 mm⁻¹
c = 13.4836 (6) Å	T = 293 K
β = 96.798 (4)°	Block, yellow
V = 615.86 (5) Å³	0.20 × 0.15 × 0.10 mm
Z = 2

Data collection top

Oxford Diffraction SuperNova (single source at offset) Eos diffractometer	1809 independent reflections
Radiation source: fine-focus sealed tube	1472 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.015
Detector resolution: 16.0454 pixels mm^-1	θ_max = 25.0°, θ_min = 3.6°
ω scans	h = −3→6
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2007)	k = −9→9
T_min = 0.951, T_max = 0.975	l = −15→16
2221 measured reflections

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.047	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.109	w = 1/[σ²(F_o²) + (0.0439P)²] where P = (F_o² + 2F_c²)/3
S = 1.06	(Δ/σ)_max = 0.009
1809 reflections	Δρ_max = 0.16 e Å⁻³
159 parameters	Δρ_min = −0.20 e Å⁻³
2 restraints	Absolute structure: Flack (1983), 640 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.04 (13)

Crystal data top

C₁₃H₁₃NO₂S	V = 615.86 (5) Å³
M_r = 247.30	Z = 2
Monoclinic, P2₁	Mo Kα radiation
a = 5.6325 (3) Å	µ = 0.25 mm⁻¹
b = 8.1666 (3) Å	T = 293 K
c = 13.4836 (6) Å	0.20 × 0.15 × 0.10 mm
β = 96.798 (4)°

Data collection top

Oxford Diffraction SuperNova (single source at offset) Eos diffractometer	1809 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2007)	1472 reflections with I > 2σ(I)
T_min = 0.951, T_max = 0.975	R_int = 0.015
2221 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.047	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.109	Δρ_max = 0.16 e Å⁻³
S = 1.06	Δρ_min = −0.20 e Å⁻³
1809 reflections	Absolute structure: Flack (1983), 640 Friedel pairs
159 parameters	Absolute structure parameter: 0.04 (13)
2 restraints

Special details top

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

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

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

	x	y	z	U_iso*/U_eq
C1	0.3932 (6)	0.8415 (4)	0.5974 (3)	0.0481 (9)
C2	0.4982 (7)	0.9033 (4)	0.5174 (3)	0.0551 (10)
H2	0.6417	0.9604	0.5289	0.066*
C3	0.3927 (7)	0.8808 (4)	0.4220 (3)	0.0562 (10)
H3	0.4663	0.9221	0.3691	0.067*
C4	0.1768 (7)	0.7970 (4)	0.4023 (3)	0.0500 (9)
C5	0.0698 (7)	0.7362 (4)	0.4812 (2)	0.0449 (9)
H5	−0.0738	0.6795	0.4689	0.054*
C6	0.1748 (6)	0.7589 (4)	0.5800 (2)	0.0415 (8)
C7	0.0515 (7)	0.6993 (4)	0.6618 (3)	0.0440 (9)
H7	−0.0921	0.6433	0.6472	0.053*
C8	−0.0063 (7)	0.6629 (5)	0.8305 (3)	0.0586 (11)
H8A	−0.1025	0.5702	0.8050	0.070*
H8B	−0.1139	0.7489	0.8468	0.070*
C9	0.1489 (7)	0.6132 (4)	0.9223 (3)	0.0506 (9)
C10	0.1217 (7)	0.6557 (5)	1.0203 (3)	0.0562 (10)
H10	0.0014	0.7232	1.0389	0.067*
C11	0.3051 (8)	0.5809 (6)	1.0888 (3)	0.0726 (13)
H11	0.3178	0.5960	1.1576	0.087*
C12	0.4554 (8)	0.4878 (7)	1.0440 (3)	0.0725 (12)
H12	0.5821	0.4302	1.0781	0.087*
C13	−0.1056 (9)	0.6748 (6)	0.2794 (3)	0.0737 (13)
H13A	−0.1514	0.6756	0.2085	0.111*
H13B	−0.2383	0.7091	0.3128	0.111*
H13C	−0.0587	0.5661	0.3004	0.111*
N1	0.1345 (6)	0.7215 (4)	0.7533 (2)	0.0528 (8)
O1	0.5060 (5)	0.8643 (3)	0.6917 (2)	0.0659 (8)
O2	0.0879 (6)	0.7829 (3)	0.30331 (18)	0.0652 (8)
S1	0.3895 (2)	0.48631 (16)	0.91768 (8)	0.0757 (4)
H1	0.386 (11)	0.814 (9)	0.743 (4)	0.17 (2)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.040 (2)	0.046 (2)	0.058 (2)	0.0053 (19)	0.0061 (18)	−0.0043 (18)
C2	0.041 (2)	0.056 (2)	0.069 (3)	−0.006 (2)	0.009 (2)	0.0000 (19)
C3	0.060 (3)	0.049 (2)	0.063 (3)	0.001 (2)	0.022 (2)	0.0059 (19)
C4	0.061 (3)	0.044 (2)	0.045 (2)	0.004 (2)	0.0071 (19)	−0.0015 (16)
C5	0.050 (2)	0.0383 (18)	0.047 (2)	−0.0017 (18)	0.0080 (17)	0.0000 (16)
C6	0.0394 (19)	0.0395 (18)	0.045 (2)	0.0054 (18)	0.0042 (16)	−0.0009 (15)
C7	0.042 (2)	0.0389 (19)	0.051 (2)	0.0017 (18)	0.0079 (18)	0.0005 (16)
C8	0.052 (2)	0.078 (3)	0.047 (2)	0.002 (2)	0.0097 (19)	0.003 (2)
C9	0.054 (2)	0.049 (2)	0.050 (2)	0.001 (2)	0.0098 (19)	0.0036 (16)
C10	0.060 (2)	0.064 (2)	0.045 (2)	0.004 (2)	0.0089 (19)	0.0020 (18)
C11	0.078 (3)	0.091 (3)	0.050 (3)	−0.005 (3)	0.011 (2)	0.003 (2)
C12	0.069 (3)	0.080 (3)	0.066 (3)	−0.001 (3)	−0.001 (2)	0.017 (3)
C13	0.087 (3)	0.086 (3)	0.045 (2)	−0.006 (3)	0.000 (2)	−0.008 (2)
N1	0.0490 (19)	0.063 (2)	0.0468 (18)	0.0014 (17)	0.0085 (15)	0.0032 (15)
O1	0.0475 (16)	0.085 (2)	0.0622 (19)	−0.0050 (16)	−0.0050 (14)	−0.0040 (15)
O2	0.085 (2)	0.0653 (17)	0.0457 (16)	−0.0113 (17)	0.0085 (15)	0.0064 (13)
S1	0.0763 (8)	0.0815 (8)	0.0709 (7)	0.0178 (7)	0.0153 (6)	−0.0011 (6)

Geometric parameters (Å, º) top

C1—O1	1.365 (4)	C8—H8A	0.9700
C1—C2	1.385 (5)	C8—H8B	0.9700
C1—C6	1.398 (5)	C9—C10	1.392 (5)
C2—C3	1.364 (5)	C9—S1	1.713 (4)
C2—H2	0.9300	C10—C11	1.438 (5)
C3—C4	1.393 (5)	C10—H10	0.9300
C3—H3	0.9300	C11—C12	1.334 (6)
C4—O2	1.374 (4)	C11—H11	0.9300
C4—C5	1.375 (5)	C12—S1	1.699 (4)
C5—C6	1.404 (4)	C12—H12	0.9300
C5—H5	0.9300	C13—O2	1.410 (5)
C6—C7	1.456 (4)	C13—H13A	0.9600
C7—N1	1.279 (4)	C13—H13B	0.9600
C7—H7	0.9300	C13—H13C	0.9600
C8—N1	1.462 (4)	O1—H1	1.10 (6)
C8—C9	1.486 (5)

O1—C1—C2	118.7 (3)	C9—C8—H8B	109.3
O1—C1—C6	121.7 (3)	H8A—C8—H8B	108.0
C2—C1—C6	119.6 (3)	C10—C9—C8	127.1 (4)
C3—C2—C1	120.4 (4)	C10—C9—S1	111.2 (3)
C3—C2—H2	119.8	C8—C9—S1	121.7 (3)
C1—C2—H2	119.8	C9—C10—C11	110.6 (4)
C2—C3—C4	121.2 (4)	C9—C10—H10	124.7
C2—C3—H3	119.4	C11—C10—H10	124.7
C4—C3—H3	119.4	C12—C11—C10	113.4 (4)
O2—C4—C5	125.3 (4)	C12—C11—H11	123.3
O2—C4—C3	115.8 (3)	C10—C11—H11	123.3
C5—C4—C3	118.8 (3)	C11—C12—S1	112.5 (3)
C4—C5—C6	120.8 (3)	C11—C12—H12	123.7
C4—C5—H5	119.6	S1—C12—H12	123.7
C6—C5—H5	119.6	O2—C13—H13A	109.5
C5—C6—C1	119.1 (3)	O2—C13—H13B	109.5
C5—C6—C7	119.4 (3)	H13A—C13—H13B	109.5
C1—C6—C7	121.5 (3)	O2—C13—H13C	109.5
N1—C7—C6	122.1 (3)	H13A—C13—H13C	109.5
N1—C7—H7	119.0	H13B—C13—H13C	109.5
C6—C7—H7	119.0	C7—N1—C8	118.2 (3)
N1—C8—C9	111.6 (3)	C1—O1—H1	106 (3)
N1—C8—H8A	109.3	C4—O2—C13	117.3 (3)
C9—C8—H8A	109.3	C12—S1—C9	92.2 (2)
N1—C8—H8B	109.3

O1—C1—C2—C3	179.0 (3)	C1—C6—C7—N1	1.1 (5)
C6—C1—C2—C3	−1.5 (5)	N1—C8—C9—C10	132.6 (4)
C1—C2—C3—C4	0.6 (5)	N1—C8—C9—S1	−49.0 (5)
C2—C3—C4—O2	179.7 (3)	C8—C9—C10—C11	178.8 (3)
C2—C3—C4—C5	−0.1 (5)	S1—C9—C10—C11	0.3 (4)
O2—C4—C5—C6	−179.3 (3)	C9—C10—C11—C12	−0.8 (6)
C3—C4—C5—C6	0.4 (5)	C10—C11—C12—S1	0.9 (5)
C4—C5—C6—C1	−1.3 (5)	C6—C7—N1—C8	177.7 (3)
C4—C5—C6—C7	177.3 (3)	C9—C8—N1—C7	149.1 (3)
O1—C1—C6—C5	−178.7 (3)	C5—C4—O2—C13	−11.4 (5)
C2—C1—C6—C5	1.8 (5)	C3—C4—O2—C13	168.9 (3)
O1—C1—C6—C7	2.7 (5)	C11—C12—S1—C9	−0.6 (4)
C2—C1—C6—C7	−176.8 (3)	C10—C9—S1—C12	0.1 (3)
C5—C6—C7—N1	−177.5 (3)	C8—C9—S1—C12	−178.5 (3)

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	1.10 (6)	1.63 (7)	2.616 (4)	147 (5)
C8—H8A···O2ⁱ	0.97	2.77	3.592 (4)	143
C2—H2···Cg1ⁱⁱ	0.93	3.00	3.631 (4)	127

Symmetry codes: (i) −x, y−1/2, −z+1; (ii) −x+1, y+1/2, −z+1.

Experimental details

Crystal data
Chemical formula	C₁₃H₁₃NO₂S
M_r	247.30
Crystal system, space group	Monoclinic, P2₁
Temperature (K)	293
a, b, c (Å)	5.6325 (3), 8.1666 (3), 13.4836 (6)
β (°)	96.798 (4)
V (Å³)	615.86 (5)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.25
Crystal size (mm)	0.20 × 0.15 × 0.10

Data collection
Diffractometer	Oxford Diffraction SuperNova (single source at offset) Eos diffractometer
Absorption correction	Multi-scan (CrysAlis PRO; Oxford Diffraction, 2007)
T_min, T_max	0.951, 0.975
No. of measured, independent and observed [I > 2σ(I)] reflections	2221, 1809, 1472
R_int	0.015
(sin θ/λ)_max (Å⁻¹)	0.594

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.109, 1.06
No. of reflections	1809
No. of parameters	159
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.16, −0.20
Absolute structure	Flack (1983), 640 Friedel pairs
Absolute structure parameter	0.04 (13)

Computer programs: CrysAlis PRO (Oxford Diffraction, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N1	1.10 (6)	1.63 (7)	2.616 (4)	147 (5)
C8—H8A···O2ⁱ	0.97	2.77	3.592 (4)	143
C2—H2···Cg1ⁱⁱ	0.93	3.00	3.631 (4)	127

Symmetry codes: (i) −x, y−1/2, −z+1; (ii) −x+1, y+1/2, −z+1.

Acknowledgements

The authors acknowledge the Faculty of Arts and Sciences, Giresun University, Turkey, for the use of the diffractometer.

References

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ISSN: 2056-9890

Volume 68| Part 9| September 2012| Page o2801

doi:10.1107/S1600536812036586

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