Syntheses, crystal structures, and properties of nickel and cadmium complexes containing imidazole derivatives

Article abstract of DOI:10.1080/00958972.2012.728590

[Ni₃(C₁₃H₉N₂O) ₅(CH₃OH)₂] (1) and [Cd(C₁₂H ₈N₃)₃] (2) were synthesized in methanol and characterized by elemental analyses, IR spectra

Full text of DOI:10.1080/00958972.2012.728590

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Syntheses, crystal structures, and
properties of nickel and cadmium
complexes containing imidazole
derivatives
a b
a
b
b
Tingting Hou
, Shumei Yue , Xiangru Yue & Jianfang Ma
a
Department of Chemistry, Changchun Normal University,
Changchun 130032, P.R. China
b
Department of Chemistry, Northeast Normal University,
Changchun 130024, P.R. China
Accepted author version posted online: 11 Sep 2012.Version of
record first published: 25 Sep 2012.
To cite this article: Tingting Hou , Shumei Yue , Xiangru Yue & Jianfang Ma (2012): Syntheses,
crystal structures, and properties of nickel and cadmium complexes containing imidazole
derivatives, Journal of Coordination Chemistry, 65:22, 3895-3902
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Journal of Coordination Chemistry
Vol. 65, No. 22, 20 November 2012, 3895–3902
Syntheses, crystal structures, and properties of nickel and
cadmium complexes containing imidazole derivatives
TINGTING HOUyz, SHUMEI YUE*y, XIANGRU YUEz and JIANFANG MAz
yDepartment of Chemistry, Changchun Normal University, Changchun 130032, P.R. China
zDepartment of Chemistry, Northeast Normal University, Changchun 130024, P.R. China
(
Received 30 May 2012; in final form 13 August 2012)
[
3 9 2 5 3 2 8 3 3
Ni (C13H N O) (CH OH) ] (1) and [Cd(C12H N ) ] (2) were synthesized in methanol and
characterized by elemental analyses, IR spectra, and X-ray diffraction. Complex 1 is trinuclear
with three unsymmetric Ni(II)’s having different coordinated environments bridged by four
oxygen atoms from five ligands. Intermolecular antiferromagnetic interactions were observed
in 1. Complex 2 is mononuclear with Cd(II) six-coordinate by six nitrogen atoms from three
bidentate HPBM anions. Complex 2 shows emission maxima in the blue region.
Keywords: Imidazole complexes; Crystal structure; UV-Vis spectrum; Magnetic properties;
Fluorescence spectrum
1. Introduction
Complexes containing benzimidazole ligands have interesting topological frame-
works and potential as function materials [1–8]. Metal complexes with
2-(2-hydroxyphenyl)benzimidazole derivatives have displayed good photoluminescence
and magnetic properties [9–14]. Huang et al. reported bright red electroluminescent
devices using europium complexes with 2-(2-pyridyl)benzimidazole [15]. Our group
synthesized blue light-emitting pyridylbenzimidazole complexes of Cd(II) and Zn(II)
[
16]. Nickel imidazole complexes have an important role in biology, optical properties,
and magnetic properties [17–19]. Photophysical properties of complexes are closely
related to their structural features, so, it is important to prepare more imidazole
complexes [20]. Continuing our research on benzimidazole ligands, herein we report the
synthesis and characterization of nickel(1) and cadmium(2) compounds derived from
2
-(2-hydroxyphenyl)benzimidazole (HPBI) and 2-(2-pyridyl)benzimidazole (HPBM)
scheme 1).
(
*
Corresponding author. Email: yuesm458@nenu.edu.cn
Journal of Coordination Chemistry
ISSN 0095-8972 print/ISSN 1029-0389 online ß 2012 Taylor & Francis
http://dx.doi.org/10.1080/00958972.2012.728590

3
896
T. Hou et al.
H
N
H
N
N
N
N
HO
HPBI
HPBM
Scheme 1. Illustration of the two ligands.
2
2
. Experimental
.1. Materials and methods
Salicylic acid, o-phenylenediamine and polyphosphoric acid (Aldrich) were used
without purification. The other reagents and complexes were synthesized according to
established procedures. UV-Vis spectra were recorded on a TU-1901 spectrometer.
Fluorescence spectra of samples were recorded on a RF-5301 spectrometer. Elemental
analyses were performed on a Perkin-Elmer 240c analyzer. IR spectra of samples were
recorded on a MAGNA-560 spectrometer. The magnetic susceptibility of 1 was
measured from 2 to 300 K with an applied field of 1000 Oe on a SQUID magnetometer
using polycrystalline samples.
2
2
.2. Syntheses
.2.1. 2-(2-Hydroxyphenyl)benzimidazole (HPBI).
A
mixture of salicylic acid
(
2.5 g, 18.1 mmol) and o-phenylenediamine (1.95 g, 18.1 mmol) was stirred in concen-
ꢀ
trated polyphosphoric acid (30 g) at 200 C for 5 h. The hot mixture was poured into
vigorously stirred cold water (200 mL). The pH of the mixture was adjusted to 7.0 by
aqueous NaOH. The precipitate was filtered and then recrystallized from ethanol as
white needle crystals (2.35 g, 61%).
2
0
.2.2. Synthesis of 1. Solutions of 0.1 mmol NiCl ꢁ 6H O in 2 mL of methanol and
2
2
.2 mmol HPBI in 20 mL methanol were mixed and then 1 mL triethylamine was added.
The solution was refluxed for 3 h, filtered, and evaporated to dryness. The residue was
dissolved in methanol. Crystals of 1 were obtained after three months. Anal. Calcd for
C H N Ni O (%): C, 60.94; H, 4.09; N, 10.61. Found (%): C, 61.03; H, 4.05;
6
7
54 10
3
9
ꢂ1
N, 10.58. IR (cm ): 1608, 1487, 1288, 467, 445.
2
0
.2.3. Synthesis of 2. Solutions of 0.1 mmol Cd(Ac) ꢁ 2H O in 3 mL of methanol and
2
2
.3 mmol HPBM in 20 mL methanol were mixed and then 1.5 mL triethylamine was
added to the solution. The mixture was refluxed for 3 h. The precipitate was filtered off
and the residue was dissolved in pyridine; crystals of 2 were obtained after 12 days.
Anal. Calcd for C H CdN O (%): C, 60.50; H, 3.78; N, 17.64. Found (%): C, 60.55;
3
6
27
9
ꢂ1
H, 3.78; N, 17.66. IR (cm ): 1610, 1500, 1475, 736, 367.

Imidazole ligands
3897
Table 1. Crystal data and structure refinement for 1 and 2.
1
2
Chemical formula
Temperature (K)
C
293(2)
0.71069
1319.33
p-1
67
H
54
N
10Ni
3
O
9
36 9
C H27CdN O
293(2)
0.71073
714.1
˚
Wavelength (A)
Formula weight
Space group
Unit cell dimensions (A,
Pa-3
˚
ꢀ
)
a
b
c
ꢀ
ꢁ
ꢂ
11.797(5)
14.688(5)
21.153(5)
96.992(5)
104.512(5)
99.257(5)
3451(2), 2
1.270
18.8554(5)
18.8554(5)
18.8554(5)
90.00
90.00
90.00
6703.6(3), 80
1.415
0.695
3
˚
Volume (A ), Z
ꢂ3
ꢂ1
Calculated density (Mg m
Absorption coefficient (mm
F(000)
Crystal size (mm )
ꢃ range for data collection ( )
Limiting indices
)
)
0.869
1364
2896
3
0.24 ꢃ 0.25 ꢃ 0.26
0.24 ꢃ 0.25 ꢃ 0.26
1.87 to 28.31
ꢂ24 ꢄ h ꢄ 24;
ꢂ13 ꢄ k ꢄ 24;
ꢂ25 ꢄ l ꢄ 24
ꢀ
1.01 to 28.32
ꢂ11 ꢄ h ꢄ 15;
ꢂ19 ꢄ k ꢄ 18;
ꢂ28 ꢄ l ꢄ 19
Reflections collected/unique
Completeness to ꢃ
Absorption correction
Refinement method
Data/restraints/parameters
21,872/16072 [R(int) ¼ 0.0361]
39,677/2778 [R(int) ¼ 0.0739]
28.32(93.4%)
Semi-empirical from equivalents
28.31(99.4%)
Semi-empirical from equivalents
2
2
Full-matrix least-squares on F
16,072/0/824
0.917
Full-matrix least-squares on F
2778/0/146
0.921
2
Goodness-of-fit on F
Final R
Final R
Dꢅmax, Dꢅmin (eA
1
1
, wR
, wR
2
2
[I 4 2ꢄ(I)]
(all data)
0.0768, 0.2457
0.1299, 0.2885
1.977 and ꢂ0.818
0.0385, 0.0926
0.0897, 0.0973
1.185 and ꢂ0.918
ꢂ3
˚
)
P
P
P
P
2
o
2
2
2
2 1/2
R
1
¼
||F
o
| ꢂ |F
c
||/ |F
o
|; wR
2
¼
[w(F ꢂ F ) ] /
[w(F ) ] .
o
c
2.3. X-ray crystallography
Suitable single crystals of 1 and 2 were grown in methanol and pyridine, respectively.
Diffraction data using ! scans with graphite monochromated Mo-Kꢀ radiation
(0.71069) were collected at 293 K. Crystals were put in fine-focus sealed tube for data
collection. A summary for crystal data and structure refinement of 1 and 2 is given in
table 1. Selected bond lengths and angles are listed in tables 2–4. The data of all
2
compounds were refined by full matrix least-squares on F and structures were solved
using SHELX 97 and refined with SHELX 97 [21].
3
3
. Results and discussion
.1. Structure description of 1
Complex 1 is a trinuclear complex crystallizing in the triclinic space group p-1 with
ꢀ
Ni(3)–Ni(2)–Ni(1) angles of 77.17(4) . As shown in figure 1, the three unsymmetric
Ni(II)’s with different coordinated environments are bridged by four oxygen atoms

3
898
T. Hou et al.
˚
Table 2. Selected bond lengths (A) for 1.
N(1)ꢂNi(1)
N(3)ꢂNi(2)
N(5)ꢂNi(2)
N(7)ꢂNi(3)
N(9)ꢂNi(3)
O(1)ꢂNi(1)
O(2)ꢂNi(1)
1.998(5)
2.002(4)
2.017(5)
2.035(5)
2.008(5)
1.941(4)
1.975(4)
O(2)ꢂNi(2)
1.988(4)
2.044(4)
2.069(4)
2.300(4)
1.996(4)
2.028(4)
2.017(4)
O(5)ꢂNi(2)
O(6)ꢂNi(3)
O(7)ꢂNi(1)
Ni(1)ꢂNi(2)
Ni(2)ꢂNi(3)
2.191(4)
2.080(4)
2.092(5)
2.9121(12)
2.8549(11)
O(3)ꢂNi(2)
O(3)ꢂNi(1)
O(3)ꢂNi(3)
O(4)ꢂNi(3)
O(4)ꢂNi(2)
O(5)ꢂNi(3)
ꢀ
Table 3. Selected angles ( ) for 1.
O(1)ꢂNi(1)ꢂO(2)
O(1)ꢂNi(1)ꢂN(1)
O(2)ꢂNi(1)ꢂN(1)
O(1)ꢂNi(1)ꢂO(3)
O(2)ꢂNi(1)ꢂO(3)
N(1)ꢂNi(1)ꢂO(3)
O(1)ꢂNi(1)ꢂO(7)
O(2)ꢂNi(1)ꢂO(7)
N(1)ꢂNi(1)ꢂO(7)
O(3)ꢂNi(1)ꢂO(7)
O(1)ꢂNi(1)ꢂNi(2)
O(2)ꢂNi(1)ꢂNi(2)
N(1)ꢂNi(1)ꢂNi(2)
O(3)ꢂNi(1)ꢂNi(2)
O(7)ꢂNi(1)ꢂNi(2)
O(2)ꢂNi(2)ꢂN(3)
O(2)ꢂNi(2)ꢂN(5)
N(3)ꢂNi(2)ꢂN(5)
O(2)ꢂNi(2)ꢂO(4)
N(3)ꢂNi(2)ꢂO(4)
N(5)ꢂN(2)ꢂO(4)
O(2)ꢂNi(2)ꢂO(3)
162.27(17)
92.33(19)
105.29(18)
93.91(17)
82.71(15)
95.28(17)
88.1(2)
N(3)ꢂNi(2)ꢂO(3)
N(5)ꢂNi(2)ꢂO(3)
O(4)ꢂNi(2)ꢂO(3)
O(4)ꢂNi(2)ꢂO(5)
N(3)ꢂNi(2)ꢂO(5)
N(5)ꢂNi(2)ꢂO(5)
O(4)ꢂNi(2)ꢂO(5)
O(3)ꢂNi(2)ꢂO(5)
O(2)ꢂNi(2)ꢂNi(3)
N(3)ꢂNi(2)ꢂNi(3)
N(5)ꢂNi(2)ꢂNi(3)
O(4)ꢂNi(2)ꢂNi(3)
O(3)ꢂNi(2)ꢂNi(3)
O(5)ꢂNi(2)ꢂNi(3)
O(2)ꢂNi(2)ꢂNi(1)
N(3)ꢂNi(2)ꢂNi(1)
N(5)ꢂNi(2)ꢂNi(1)
O(4)ꢂNi(2)ꢂNi(1)
O(3)ꢂNi(2)ꢂNi(1)
O(5)ꢂNi(2)ꢂNi(1)
Ni(3)ꢂNi(2)ꢂNi(1)
O(4)ꢂNi(3)ꢂN(9)
161.58(16)
89.83(17)
82.64(15)
84.75(15)
90.76(16)
161.27(17)
81.00(14)
71.61(15)
118.09(11)
117.50(13)
121.35(13)
44.36(10)
52.91(10)
44.76(10)
42.52(11)
120.94(13)
109.49(13)
120.14(11)
45.28(10)
59.03(11)
77.17(4)
O(4)ꢂNi(3)ꢂO(5)
N(9)ꢂNi(3)ꢂO(5)
O(4)ꢂNi(3)ꢂN(7)
N(9)ꢂNi(3)ꢂN(7)
O(5)ꢂNi(3)ꢂN(7)
O(4)ꢂNi(3)ꢂO(6)
N(9)ꢂNi(3)ꢂO(6)
O(5)ꢂNi(3)ꢂO(6)
N(7)ꢂNi(3)ꢂO(6)
O(4)ꢂNi(3)ꢂO(3)
N(9)ꢂNi(3)ꢂO(3)
O(5)ꢂNi(3)ꢂO(3)
N(7)ꢂNi(3)ꢂO(3)
O(6)ꢂNi(3)ꢂO(3)
O(4)ꢂNi(3)ꢂNi(2)
N(9)ꢂNi(3)ꢂNi(2)
O(5)ꢂNi(3)ꢂNi(2)
N(7)ꢂNi(3)ꢂNi(2)
O(6)ꢂNi(3)ꢂNi(2)
O(3)ꢂNi(3)ꢂNi(2)
86.22(15)
90.58(19)
89.68(17)
105.7(2)
163.46(17)
169.72(16)
92.90(19)
86.08(17)
95.79(18)
77.12(14)
158.71(17)
69.79(14)
93.68(16)
93.82(15)
45.26(10)
115.64(15)
49.90(11)
117.81(14)
124.58(12)
45.15(9)
91.4(2)
97.7(2)
166.80(19)
125.72(13)
42.87(11)
119.37(14)
44.58(10)
124.99(16)
90.26(16)
95.66(17)
107.95(18)
162.36(15)
100.24(17)
94.54(16)
83.04(15)
93.98(18)
˚
Table 4. Selected bond lengths (A) and angles ( ) for 2.
ꢀ
Cd(1)ꢂN(1)
Cd(1)ꢂN(2)
2.253(3)
2.488(3)
N(1)ꢂCd(1)ꢂN(1)
N(1)ꢂCd(1)ꢂN(2)
N(1)ꢂCd(1)ꢂN(2)
N(1)ꢂCd(1)ꢂN(2)
N(2)ꢂCd(1)ꢂN(2)
105.47(8)
71.26(10)
156.57(9)
97.64(9)
86.00(10)
from five ligands. The Ni(1)ꢁ ꢁ ꢁNi(2) and Ni(2)ꢁ ꢁ ꢁNi(3) distances (2.9121(12) and
.8549(11)) reveal that there is no direct metal–metal interaction [22]. Seven oxygen
atoms involved in coordination come from methanol and HPBI; O(2), O(3) O(4),
2
and O(5) are bridging. The Ni–N and Ni–O bond distances are 1.998–2.002 and
˚
1
.941–2.300 A, respectively, comparable to literature values [23, 24].
We have reviewed the literature for Co(II), Mn(IV), Zn(II), and Cu(II) complexes of
ligand HPBI [12, 14, 25]. Complexes of Co(II), Zn(II), and Cu(II) of HPBI are
mononuclear with tetrahedral center ions coordinated by two deprotonated HPBI. The
Mn(IV) complex of HPBI is binuclear with two six-coordinate manganese(IV) ions
coordinated to two HPBI ligands and bridged by two oxides. Complex 1 is a new

Imidazole ligands
3899
Figure 1. Molecule structure of 1.
trinuclear complex, much more complicated, probably due to the relatively small ion
radius creating hindrance and the presence of bridging oxygen atoms.
3.2. Structure description of 2
As shown in figure 2, each Cd(II) is six-coordinate by six nitrogen atoms from the three
bidentate HPBM anions. The coordination geometry of Cd(II) is distorted octahedral.
Each deprotonated HPBM coordinates to one Cd(II) through pyridine N and imidazole
˚
N. The Cd–N (pyridine) distance of (2.488 A) is longer than the Cd–N (imidazole)
˚
distance (2.253 A).
In 2006, Yue and co-workers reported a Cd(II) complex of HPBM [Cd(L2) (H O) ]
2
2
2
with Cd(II) six-coordinate by four nitrogen atoms from the two bidentate HPBM
anions and two water molecules [16]. There are no water molecules in 2, which is a
relatively stable structure.
3
.3. Photophysical properties
The UV-Vis absorption spectra of HPBI, HPBM, 1, and 2 were recorded at
ꢂ5
ꢂ1
1
HPBI and 1 are shown in ‘‘Supplementary material’’ section. The spectrum of 1 is
.0ꢃ10 mol L in methanol at room temperature. The UV-Vis spectra of ligand
similar with HPBI, but red-shifted 13 nm from formation of the complex altering the

3
900
T. Hou et al.
Figure 2. Molecule structure of 2.
conjugated system. Compared with HPBI, the emissions of 1 blue shift (Supplementary
material), indicating that in dilute solutions the intermolecular interactions between 1
are much weaker than between HPBI. The chelate structure may decrease the
intermolecular interaction.
The UV-Vis spectra of ligand HPBM and 2 are also shown in ‘‘Supplementary
material’’ section. The maximum absorptions of HPBM and 2 are 308 nm and 309 nm,
assigned to intraligand ꢆ–ꢆ* transitions.
As shown in figure 3, the maximum emissions of HPBM and 2 are 418 nm and
35 nm, respectively, red-shifted for 2 compared to HPBM. This is assigned to ꢆ–ꢆ*
4
fluorescence and Cd has no contribution to the light-emitting. The metals increase
ligand rigidity, improving luminescent properties.
In 2006, Yue and co-workers researched the luminescent properties of
[
Cd(L2) (H O) ], which is a rare blue fluorescent material [16]. They reported the
2 2 2
effect of water on zinc(II) and cadmium(II) complexes with pyridylimidazole by (DFT)
B3LYP methods with coordinated water, resulting in low photoluminescent quantum
efficiency [20]. Complex 2 has water replaced by HPBM allowing 2 to have improved
luminescent properties. In future, 2 will be studied for electroluminescent display.
3
.4. Magnetic properties
The X T versus T curve of 1 suggests a weak intramolecular antiferromagnetic
M
interaction between Ni(II) ions as shown in figure 4. The value of X T at 300 K is
M
3
ꢂ1
.2257 cm mol K. When the temperature decreases, the X T values remain basically
M
1
unchanged until 50 K, when X T values decrease rapidly reaching a value of
M

Imidazole ligands
3901
Figure 3. Emission spectra of HPBM and 2.
ꢂ1
Figure 4. Plots of X
M
T vs. T and XM vs. T for 1.
3
.5223 cm mol K at 2 K. The magnetic data for 1 can be fitted to the Curie–Weiss law
ꢂ1
0
3
ꢂ1
X ¼ C/(T ꢂ ꢃ), with C ¼ 1.474 cm mol K and ꢃ ¼ ꢂ5.49 K. The negative ꢃ value for
M
1
indicates antiferromagnetic interactions between Ni(II) ions.
4. Conclusion
Two new complexes, [Ni (C H N O) (CH OH) ] (1) and [Cd(C H N ) ] (2), were
3
13
9
2
5
3
2
12
8
3 3
synthesized in methanol and characterized. Complex 1 is trinuclear while 2 is

3
902
T. Hou et al.
mononuclear. Compared with reported Zn(II), Cu(II), Co(II), and Mn(IV) complexes,
the structures of 1 and 2 are more complicated. We reported magnetic properties of 1
and luminescent properties of 2. Metal ions play significant roles in determining the
structure and properties of these complexes.
Supplementary material
Crystallographic data for the structural analyses have been deposited with the
Cambridge Crystallographic Data Center, CCDC Nos 881784 and 881783 for 1 and
2
, respectively. Copies of this information may be obtained free of charge from The
Director, CCDC, 12 Union Road, Cambridge CB21EZ, UK (Fax: þ44-1223-336033;
E-mail: deposit@ccdc.cam.ac.uk or http://www.ccdc.cam.ac.uk).
Acknowledgments
The authors gratefully acknowledge the Ministry of Education of the People’s Republic
of China (No. 208034) and Jilin Provincial Department of Education project
(Nos. 2009-203 and 2011-192) for the financial support.
References
[
[
[
[
[
[
[
1] S.R. Batten, R. Robson. Angew. Chem. Int. Ed., 37, 1460 (1998).
2] M.M. Henary, C.J. Fahrni. J. Phys. Chem. A, 106, 5210 (2002).
3] D.H. Pierre, F. Daniel. Chem. Soc. Rev., 171, 351 (1998).
4] S. Kitagawa, R. Kitaura, S.I. Noro. Angew. Chem. Int. Ed., 43, 2334 (2004).
5] D. Maspoch, D. Ruiz-Molina, J. Veciana. J. Mater. Chem., 14, 2713 (2004).
6] S.R. Batten, K.S. Murray. Coord. Chem. Rev., 246, 103 (2003).
7] Y. He, B. Wu, J. Yang, D. Robinson, L. Risen, R. Ranken, L. Blyn, S. Sheng, E. Swayze. Bioorg. Med.
Chem. Lett., 13, 3915 (2003).
[
8] K. Wang, L. Huang, L. Gao, C. Huang, L. Jin. Solid State Commun., 122, 233 (2002).
9] F.Z.C. Fellah, J.P. Costes, C. Duhayon, J.C. Daran, J.P. Tuchagues. Polyhedron, 29, 2111 (2010).
[
10] J.D. Crane, E. Sinn, B. Tann. Polyhedron, 18, 1527 (1999).
[
[
[
[
[
[
[
11] Y. Xi, M. Jiang, J. Li, C. Wang, J.F. Yan, F.X. Zhang. Acta Chim. Sin., 64, 1183 (2006).
¨
12] M.Y. Duan, J. Li, Y. Xi, X.F. Lu, J.Z. Liu, G. Mele, F.X. Zhang. J. Coord. Chem., 63, 90 (2010).
13] H. Chang, M. Fu, X.J. Zhao, E.C. Yang. J. Coord. Chem., 63, 3551 (2010).
14] Y.P. Tong, S.L. Zheng, X.M. Chen. Eur. J. Inorg. Chem., 3734 (2005).
15] L. Huang, K.Z. Wang, C.H. Huang, F.Y. Li, Y.Y. Huang. J. Mater. Chem., 11, 790 (2001).
16] (a) S.M. Yue, N. Li, J.Y. Bian, T.T. Hou, J.F. Ma. Synth. Met., 162, 247 (2012); (b) S.M. Yue, H.B. Xu,
J.F. Ma, Z.M. Su, Y.H. Kan, H.J. Zhang. Polyhedron, 25, 636 (2006).
[
[
[
[
[
17] W.P. Jia, J.G. Yang, F. Li. Chin. J. Inorg. Chem., 24, 627 (2008).
18] M.X. Li, Z. Xu, X.Z. You. Polyhedron, 12, 921 (1993).
19] M. Alexiou, I. Tsivikas, C. Dendrinou-Samara. J. Inorg. Biochem., 93, 256 (2003).
20] Y. Liao, Z.M. Su, Y.H. Kan, S.M. Yue, J.F. Ma, J.H. Yang. Int. J. Quantum Chem., 106, 490 (2006).
21] G.M. Sheldrick. SHELXS 97, Program for Crystal Structure Solution, University of Gottingen, Germany
(1997).
[22] K. Matsumoto, I. Nakanishi, H. Nakano, S. Ooi. Polyhedron, 15, 4501 (1996).
[23] N. Hoshino, T. Ito, M. Nihei, H. Oshio. Synth. Met., 137, 1309 (2003).
[24] H. Adams, S. Clunas, D.E. Fenton, T.J. Gregson, P.E. McHugh. Inorg. Chem. Commun., 5, 211 (2002).
[25] Y. Xi, J. Li, F.X. Zhang. Acta Cryst., E61, 1953 (2005).