catena-Poly[[[triaqua­copper(II)]-μ2-pyrazine-2,3-dicarboxyl­ato] monohydrate]

Wu, W.-P.; Zeng, F.-C.; Wu, Y.; Peng, J.

doi:10.1107/S1600536807062800

metal-organic compounds

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ISSN: 2056-9890

Volume 64| Part 1| January 2008| Page m61

https://doi.org/10.1107/S1600536807062800

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catena-Poly[[[triaquacopper(II)]-μ₂-pyrazine-2,3-dicarboxylato] monohydrate]

Wei-Ping Wu,^a ^* Feng-Chun Zeng,^a Yu Wu ^a and Jian Peng ^b

^aDepartment of Chemistry, Sichuan University of Science and Engineering, Zigong, 643000, People's Republic of China, and ^bDepartment of Materials and Chemical Engineering, Sichuan University of Science and Engineering, Zigong 643000,People's Republic of China
^*Correspondence e-mail: wuweipingzg@126.com

(Received 16 November 2007; accepted 24 November 2007; online 6 December 2007)

The Cu atom in the title complex, {[Cu(C₆H₂N₂O₄)(H₂O)₃]·H₂O}_n or {[Cu(L)(H₂O)₃]·H₂O}_n (L is pyrazine-2,3-dicarboxylate), displays octahedral coordination formed by the ligand L and three coordinated water molecules. The ligand L is tridentate, with one N atom of the pyrazine ring and one O atom of one carboxylate group forming a chelate ring, whereas one O atom from the second carboxylate group is coordinated to another Cu atom. The ligand L links molecules to form an infinite chain parallel to the [101] direction. The chains are further linked through O—H⋯O and O—H⋯N hydrogen bonds involving the water molecules to build up a three-dimensional network.

Related literature

For related literature, see: Gokel et al. (2004 ); Shan et al. (2001 ); Starosta & Leciejewicz (2005 ); Takusagawa & Shimada (1973 ); Tombul et al. (2007 ); Ptasiewicz-Bak & Leciejewicz (1997a ,b ).

Experimental

Crystal data

[Cu(C₆H₂N₂O₄)(H₂O)₃]·H₂O
M_r = 301.70
Monoclinic, C c
a = 8.4254 (4) Å
b = 18.0692 (8) Å
c = 7.4187 (3) Å
β = 114.4120 (10)°
V = 1028.45 (8) Å³
Z = 4
Mo Kα radiation
μ = 2.16 mm⁻¹
T = 298 (2) K
0.28 × 0.25 × 0.17 mm

Data collection

Bruker APEXII area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2004 ) T_min = 0.519, T_max = 0.660
3079 measured reflections
1683 independent reflections
1654 reflections with I > 2σ(I)
R_int = 0.067

Refinement

R[F² > 2σ(F²)] = 0.036
wR(F²) = 0.089
S = 1.11
1683 reflections
156 parameters
2 restraints
H-atom parameters constrained
Δρ_max = 0.67 e Å⁻³
Δρ_min = −1.08 e Å⁻³
Absolute structure: Flack (1983 ), 758 Friedel pairs
Flack parameter: −0.04 (2)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O5—H5A⋯O7ⁱ	0.84	2.30	2.953 (4)	134
O5—H5B⋯O8	0.86	1.79	2.630 (6)	168
O6—H6A⋯O4ⁱⁱ	0.85	1.98	2.837 (4)	176
O6—H6A⋯O3ⁱⁱ	0.85	2.57	3.170 (5)	128
O6—H6B⋯O4ⁱⁱⁱ	0.84	1.87	2.691 (4)	167
O7—H7A⋯N2ⁱⁱⁱ	0.83	1.98	2.817 (5)	177
O7—H7B⋯O1^iv	0.83	1.90	2.719 (6)	166
O8—H8A⋯O4^iv	0.85	2.02	2.864 (6)	176
O8—H8B⋯O1^v	0.85	2.11	2.898 (6)	155
Symmetry codes: (i) $[x, -y, z+{\script{1\over 2}}]$ ; (ii) $[x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ ; (iii) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (iv) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (v) $[x-{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ .

Data collection: APEX2 (Bruker, 2004 ); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Burnett & Johnson, 1996 ) and PLATON (Spek, 2003 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536807062800/dn2285sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536807062800/dn2285Isup2.hkl

checkCIF report

Comment top

Transition metal complexes with bipyridine derivatives are suitable models for the study of excited state dynamics. In addition, they are of interest for the development of light-energy conversion devices and optical sensors (Gokel et al., 2004; Shan et al., 2001). Since the single-crystal X-ray analysis of pyrazine-2,3 dicarboxylic acid was first determined (Takusagawa & Shimada, 1973), a variety of metal-organic compounds of pyrazine-2,3-dicarboxylic acid have been characterized crystallographically, due to growing interest in supramolecular chemistry (Tombul et al., 2007). These include the calcium (Ptasiewicz-Bak & Leciejewicz, 1997a; Starosta & Leciejewicz, 2005) and magnesium (Ptasiewicz-Bak & Leciejewicz, 1997b) complexes. In this paper, we report the synthesis and crystal structure of the title complex,(I).

The Cu^II ion displays octahedral coordination formed by the one L ligand and three coordinated water molecules. The ligand L is tridentate with the N atom of the pyridine ring and one O atom of one carboxylate forming a chelate ring whereas one O atom from the second carboxylate is coordinated to another Cu atom (Fig. 1). Then the ligand L links molecules to form an infinite chain parallel to the [1 O 1] direction. The chains are further linked through O—H···O and O—H···N involving the water molecules to build up a three dimensionnal network (Table 1).

Related literature top

For related literature, see: Gokel et al. (2004); Shan et al. (2001); Starosta & Leciejewicz (2005); Takusagawa & Shimada (1973); Tombul et al. (2007); Ptasiewicz-Bak & Leciejewicz (1997a,b).

Experimental top

L (0.031 g, 0.018 mmol), CuSO4 (0.018 g, 0.016 mmol) and NaOH(0.048 mmol,0.12 mmol), were added in a mixed solvent of ethanol, the mixture was heated for three hours under reflux. during the process stirring and influx were required. The resultant was then filtered to give a pure solution which was infiltrated by diethyl ether freely in a closed vessel, two weeks later some single crystals of the size suitable for X-Ray diffraction analysis.

Structure description top

For related literature, see: Gokel et al. (2004); Shan et al. (2001); Starosta & Leciejewicz (2005); Takusagawa & Shimada (1973); Tombul et al. (2007); Ptasiewicz-Bak & Leciejewicz (1997a,b).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2003); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures top

Fig. 1. View of compound (I) with the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms have been omitted for clarity. [Symmetry codes: (i) x - 1/2, 1/2 - y, z - 1/2; (ii) 1/2 + x, 1/2 - y, 1/2 + z]

catena-Poly[[[triaquacopper(II)]-µ₂-pyrazine-2,3-dicarboxylato] monohydrate] top

Crystal data top

[Cu(C₆H₂N₂O₄)(H₂O)₃]·H₂O	F(000) = 612
M_r = 301.70	D_x = 1.949 Mg m⁻³
Monoclinic, Cc	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C -2yc	Cell parameters from 1683 reflections
a = 8.4254 (4) Å	θ = 2.3–25.2°
b = 18.0692 (8) Å	µ = 2.16 mm⁻¹
c = 7.4187 (3) Å	T = 298 K
β = 114.412 (1)°	Block, blue
V = 1028.45 (8) Å³	0.28 × 0.25 × 0.17 mm
Z = 4

Data collection top

Bruker APEXII area-detector diffractometer	1683 independent reflections
Radiation source: fine-focus sealed tube	1654 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.067
φ and ω scan	θ_max = 25.2°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	h = −10→9
T_min = 0.519, T_max = 0.660	k = −21→20
3079 measured reflections	l = −8→8

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)] = 0.036	H-atom parameters constrained
wR(F²) = 0.089	w = 1/[σ²(F_o²) + (0.0632P)²] where P = (F_o² + 2F_c²)/3
S = 1.11	(Δ/σ)_max < 0.001
1683 reflections	Δρ_max = 0.67 e Å⁻³
156 parameters	Δρ_min = −1.08 e Å⁻³
2 restraints	Absolute structure: Flack (1983), 758 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.04 (2)

Crystal data top

[Cu(C₆H₂N₂O₄)(H₂O)₃]·H₂O	V = 1028.45 (8) Å³
M_r = 301.70	Z = 4
Monoclinic, Cc	Mo Kα radiation
a = 8.4254 (4) Å	µ = 2.16 mm⁻¹
b = 18.0692 (8) Å	T = 298 K
c = 7.4187 (3) Å	0.28 × 0.25 × 0.17 mm
β = 114.412 (1)°

Data collection top

Bruker APEXII area-detector diffractometer	1683 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	1654 reflections with I > 2σ(I)
T_min = 0.519, T_max = 0.660	R_int = 0.067
3079 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.036	H-atom parameters constrained
wR(F²) = 0.089	Δρ_max = 0.67 e Å⁻³
S = 1.11	Δρ_min = −1.08 e Å⁻³
1683 reflections	Absolute structure: Flack (1983), 758 Friedel pairs
156 parameters	Absolute structure parameter: −0.04 (2)
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
Cu1	0.89418 (3)	0.118643 (19)	0.89933 (3)	0.02206 (17)
N1	0.6873 (5)	0.18186 (18)	0.9306 (5)	0.0277 (8)
N2	0.4368 (5)	0.2821 (2)	0.9255 (5)	0.0289 (10)
O1	0.9124 (6)	0.34477 (15)	0.9145 (8)	0.0380 (8)
O2	0.9816 (4)	0.22606 (16)	0.9101 (5)	0.0311 (7)
O3	0.5382 (5)	0.40933 (18)	0.6974 (4)	0.0347 (8)
O4	0.6390 (5)	0.42851 (17)	1.0176 (4)	0.0346 (7)
O5	0.7715 (5)	0.01798 (16)	0.8841 (6)	0.0428 (8)
H5A	0.8168	−0.0080	0.9872	0.064*
H5B	0.6618	0.0110	0.8202	0.064*
O6	1.1011 (4)	0.07381 (17)	0.8605 (4)	0.0314 (7)
H6A	1.1120	0.0292	0.9021	0.047*
H6B	1.1000	0.0780	0.7471	0.047*
O7	0.7584 (5)	0.12285 (15)	0.5794 (5)	0.0302 (8)
H7A	0.8141	0.1510	0.5379	0.039 (15)*
H7B	0.6501	0.1250	0.5249	0.033 (16)*
C1	0.8817 (8)	0.2773 (2)	0.9095 (8)	0.0247 (9)
C2	0.7074 (6)	0.2543 (2)	0.9108 (6)	0.0229 (9)
C3	0.5804 (6)	0.3047 (2)	0.9043 (6)	0.0232 (9)
C4	0.4209 (6)	0.2097 (3)	0.9474 (6)	0.0328 (10)
H4	0.3237	0.1927	0.9642	0.039*
C5	0.5417 (6)	0.1592 (2)	0.9461 (6)	0.0322 (10)
H5	0.5227	0.1089	0.9561	0.039*
C7	0.5890 (6)	0.3869 (2)	0.8690 (7)	0.0226 (9)
O8	0.4396 (6)	−0.0183 (3)	0.7257 (8)	0.0755 (15)
H8A	0.3537	0.0099	0.6642	0.113*
H8B	0.4043	−0.0601	0.7463	0.113*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cu1	0.0207 (2)	0.0188 (2)	0.0264 (2)	0.0014 (2)	0.00942 (17)	−0.00095 (19)
N1	0.028 (2)	0.0247 (17)	0.0301 (16)	−0.0003 (15)	0.0116 (15)	0.0023 (14)
N2	0.023 (3)	0.0329 (18)	0.031 (2)	−0.0011 (14)	0.0125 (18)	−0.0029 (15)
O1	0.0243 (17)	0.0237 (14)	0.065 (2)	−0.0024 (14)	0.0179 (14)	0.0017 (17)
O2	0.0231 (17)	0.0236 (14)	0.0479 (16)	0.0006 (13)	0.0160 (14)	−0.0014 (13)
O3	0.0441 (19)	0.0313 (16)	0.0264 (15)	−0.0016 (15)	0.0122 (13)	0.0034 (12)
O4	0.049 (2)	0.0275 (14)	0.0286 (14)	−0.0017 (14)	0.0175 (14)	−0.0071 (12)
O5	0.0312 (17)	0.0303 (16)	0.0567 (19)	−0.0052 (14)	0.0080 (14)	0.0110 (15)
O6	0.0317 (16)	0.0314 (14)	0.0324 (13)	0.0075 (14)	0.0145 (12)	0.0045 (13)
O7	0.0225 (18)	0.0338 (18)	0.0320 (19)	−0.0006 (11)	0.0088 (15)	0.0049 (11)
C1	0.020 (2)	0.0256 (18)	0.0268 (16)	−0.004 (2)	0.0080 (14)	−0.0001 (18)
C2	0.022 (2)	0.0225 (19)	0.0215 (17)	−0.0037 (16)	0.0063 (15)	−0.0012 (14)
C3	0.019 (2)	0.027 (2)	0.0194 (16)	−0.0031 (16)	0.0039 (14)	−0.0017 (15)
C4	0.029 (3)	0.035 (2)	0.042 (3)	−0.009 (2)	0.023 (2)	−0.0048 (16)
C5	0.034 (3)	0.0257 (19)	0.039 (2)	−0.0028 (19)	0.0162 (18)	−0.0010 (17)
C7	0.020 (2)	0.025 (2)	0.024 (2)	0.0004 (15)	0.0112 (17)	−0.0018 (14)
O8	0.031 (2)	0.062 (3)	0.102 (3)	−0.0071 (18)	−0.004 (2)	0.021 (2)

Geometric parameters (Å, º) top

Cu1—O6	2.048 (3)	O5—H5A	0.8422
Cu1—O2	2.066 (3)	O5—H5B	0.8559
Cu1—O5	2.072 (3)	O6—H6A	0.8539
Cu1—O3ⁱ	2.098 (3)	O6—H6B	0.8410
Cu1—O7	2.169 (4)	O7—H7A	0.8328
Cu1—N1	2.175 (4)	O7—H7B	0.8323
N1—C2	1.335 (5)	C1—C2	1.530 (7)
N1—C5	1.343 (7)	C2—C3	1.391 (6)
N2—C4	1.332 (6)	C3—C7	1.515 (5)
N2—C3	1.347 (6)	C4—C5	1.369 (7)
O1—C1	1.244 (5)	C4—H4	0.9300
O2—C1	1.249 (6)	C5—H5	0.9300
O3—C7	1.232 (6)	O8—H8A	0.8483
O3—Cu1ⁱⁱ	2.098 (3)	O8—H8B	0.8472
O4—C7	1.255 (5)

O6—Cu1—O2	93.81 (13)	Cu1—O6—H6B	116.5
O6—Cu1—O5	94.56 (15)	H6A—O6—H6B	113.7
O2—Cu1—O5	171.41 (14)	Cu1—O7—H7A	107.6
O6—Cu1—O3ⁱ	84.14 (13)	Cu1—O7—H7B	120.6
O2—Cu1—O3ⁱ	98.28 (13)	H7A—O7—H7B	117.6
O5—Cu1—O3ⁱ	84.50 (14)	O1—C1—O2	126.5 (6)
O6—Cu1—O7	87.38 (13)	O1—C1—C2	117.0 (5)
O2—Cu1—O7	91.59 (12)	O2—C1—C2	116.5 (4)
O5—Cu1—O7	86.87 (14)	N1—C2—C3	121.0 (4)
O3ⁱ—Cu1—O7	167.38 (13)	N1—C2—C1	115.6 (4)
O6—Cu1—N1	171.52 (13)	C3—C2—C1	123.2 (4)
O2—Cu1—N1	77.94 (13)	N2—C3—C2	120.8 (4)
O5—Cu1—N1	93.62 (15)	N2—C3—C7	115.3 (4)
O3ⁱ—Cu1—N1	98.85 (14)	C2—C3—C7	123.9 (4)
O7—Cu1—N1	90.86 (14)	N2—C4—C5	122.8 (5)
C2—N1—C5	118.1 (4)	N2—C4—H4	118.6
C2—N1—Cu1	111.0 (3)	C5—C4—H4	118.6
C5—N1—Cu1	130.5 (3)	N1—C5—C4	120.3 (4)
C4—N2—C3	116.9 (4)	N1—C5—H5	119.8
C1—O2—Cu1	117.8 (3)	C4—C5—H5	119.8
C7—O3—Cu1ⁱⁱ	144.4 (3)	O3—C7—O4	123.9 (4)
Cu1—O5—H5A	114.2	O3—C7—C3	118.7 (4)
Cu1—O5—H5B	124.0	O4—C7—C3	117.3 (4)
H5A—O5—H5B	113.7	H8A—O8—H8B	110.3
Cu1—O6—H6A	107.0

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5A···O7ⁱⁱⁱ	0.84	2.30	2.953 (4)	134
O5—H5B···O8	0.86	1.79	2.630 (6)	168
O6—H6A···O4^iv	0.85	1.98	2.837 (4)	176
O6—H6A···O3^iv	0.85	2.57	3.170 (5)	128
O6—H6B···O4^v	0.84	1.87	2.691 (4)	167
O7—H7A···N2^v	0.83	1.98	2.817 (5)	177
O7—H7B···O1ⁱⁱ	0.83	1.90	2.719 (6)	166
O8—H8A···O4ⁱⁱ	0.85	2.02	2.864 (6)	176
O8—H8B···O1^vi	0.85	2.11	2.898 (6)	155

Symmetry codes: (ii) x−1/2, −y+1/2, z−1/2; (iii) x, −y, z+1/2; (iv) x+1/2, y−1/2, z; (v) x+1/2, −y+1/2, z−1/2; (vi) x−1/2, y−1/2, z.

Experimental details

Crystal data
Chemical formula	[Cu(C₆H₂N₂O₄)(H₂O)₃]·H₂O
M_r	301.70
Crystal system, space group	Monoclinic, Cc
Temperature (K)	298
a, b, c (Å)	8.4254 (4), 18.0692 (8), 7.4187 (3)
β (°)	114.412 (1)
V (Å³)	1028.45 (8)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	2.16
Crystal size (mm)	0.28 × 0.25 × 0.17

Data collection
Diffractometer	Bruker APEXII area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2004)
T_min, T_max	0.519, 0.660
No. of measured, independent and observed [I > 2σ(I)] reflections	3079, 1683, 1654
R_int	0.067
(sin θ/λ)_max (Å⁻¹)	0.598

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.036, 0.089, 1.11
No. of reflections	1683
No. of parameters	156
No. of restraints	2
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.67, −1.08
Absolute structure	Flack (1983), 758 Friedel pairs
Absolute structure parameter	−0.04 (2)

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEPIII (Burnett & Johnson, 1996) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5A···O7ⁱ	0.84	2.30	2.953 (4)	134.4
O5—H5B···O8	0.86	1.79	2.630 (6)	167.8
O6—H6A···O4ⁱⁱ	0.85	1.98	2.837 (4)	175.8
O6—H6A···O3ⁱⁱ	0.85	2.57	3.170 (5)	128.2
O6—H6B···O4ⁱⁱⁱ	0.84	1.87	2.691 (4)	166.8
O7—H7A···N2ⁱⁱⁱ	0.83	1.98	2.817 (5)	177.1
O7—H7B···O1^iv	0.83	1.90	2.719 (6)	165.9
O8—H8A···O4^iv	0.85	2.02	2.864 (6)	176.2
O8—H8B···O1^v	0.85	2.11	2.898 (6)	154.7

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

Acknowledgements

The authors are grateful to Sichuan University for financial support.

References

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