NMR (1D and 2D) and X-ray crystallographic studies of Ni(II) complex with N-(2-mercaptophenyl)-4-methoxysalicylideneimine and triphenylphosphine

Article abstract of DOI:10.1016/j.saa.2010.06.004

Mononuclear nickel(II) complex, viz. [Ni(L)(PPh₃)] (where L is dianion of N-(2-mercaptophenyl)-4-methoxysalicylideneimine) has been synthesized and characterized by means of elemental analysis, electronic, IR and NMR [ ¹H, ¹³C{¹H} and ³¹P{¹H}, DEPT, ¹H-¹H COSY, ge-HSQC, ge-HMBC] spectroscopic techniques. Structural analysis of the complex by single crystal X-ray crystallography indicated the presence of square planar coordination geometry (ONSP) about nickel. One of the phenyl rings of triphenylphosphine involve in CH...π interactions with H6b, H13 and H32 to form a three dimensional network which stabilizes the structure of complex.

Full text of DOI:10.1016/j.saa.2010.06.004

Spectrochimica Acta Part A 77 (2010) 411–418
Contents lists available at ScienceDirect
Spectrochimica Acta Part A: Molecular and
Biomolecular Spectroscopy
journal homepage: www.elsevier.com/locate/saa
NMR (1D and 2D) and X-ray crystallographic studies of Ni(II) complex with
N-(2-mercaptophenyl)-4-methoxysalicylideneimine and triphenylphosphine
M. Muthu Tamizha, B. Vargheseb, A. Endoc, R. Karvembua,∗
a Department of Chemistry, National Institute of Technology, Tiruchirappalli 620015, India
b Sophisticated Analytical Instruments Facility, Indian Institute of Technology-Madras, Chennai 600036, India
c Department of Materials and Life Sciences, Sophia University, Tokyo 102-8554, Japan
a r t i c l e i n f o
a b s t r a c t
Article history:
Mononuclear nickel(II) complex, viz. [Ni(L)(PPh3)] (where L is dianion of N-(2-mercaptophenyl)-4-
Received 3 February 2010
Received in revised form 22 May 2010
Accepted 4 June 2010
methoxysalicylideneimine) has been synthesized and characterized by means of elemental analysis,
1
1
electronic, IR and NMR [1H, 13C{ H} and 31P{ H}, DEPT, 1H–1H COSY, ge-HSQC, ge-HMBC] spectro-
scopic techniques. Structural analysis of the complex by single crystal X-ray crystallography indicated
the presence of square planar coordination geometry (ONSP) about nickel. One of the phenyl rings of
triphenylphosphine involve in C H· · ·␲ interactions with H6b, H13 and H32 to form a three dimensional
network which stabilizes the structure of complex.
This paper is dedicated to Professor K.
Natarajan on the occasion of his 60th
birthday.
© 2010 Elsevier B.V. All rights reserved.
Keywords:
Salicylideneimine
Ni(II) complex
2D NMR
Crystal structure
1. Introduction
2. Experimental
A large number of Schiff base complexes have been studied for
their interesting and important properties such as their ability to
reversibly bind oxygen [1], catalytic activity in hydrogenation of
olefins [2], transfer of an amino group [3], photochromic prop-
erties [4], complexing ability towards some toxic metals [5], etc.
They also exhibit interesting stereochemical, electrochemical and
electronic properties [6]. Complexation of nickel by Schiff base
ligands with N, S donor atoms has been of particular interest
because of the fact that coordination sphere of nickel in metal-
loproteins such as 2-mercaptoethanol-inhibited urease and Ni/Fe
hydrogenases contains N and S donor sets. Recently we devoted
our efforts to the synthesis of several Schiff base complexes with
nickel to obtain information on the chemical behaviour of the
metal with these ligands [7]. In continuation of our efforts, we
herein report the synthesis, spectral studies including detailed 2D
NMR and crystal structure of Ni(II) complex containing dianion
of N-(2-mercaptophenyl)-4-methoxysalicylideneimine) and triph-
enylphosphine (Scheme 1).
2.1. Materials and methods
All the reagents and solvents employed were commercially
available and used with no further purification. Schiff base ligands
[8] and [NiCl2(PPh3)2] [9] were prepared by following literature
method.
2.2. Physical measurements
Electronic spectrum was measured on a PerkinElmer EZ 301
UV–vis double beam spectrophotometer in CH3CN solution of the
complex in the 200–800 nm range. FT-IR spectrum was recorded
on a PerkinElmer Spectrum One FT-IR spectrometer as KBr pel-
let in the frequency range of 400–4000 cm−1. The C, H, N and S
contents were determined by Thermoflash EA1112 series elemen-
tal analyzer. The 1H and 13C{ H} NMR spectrum were recorded
1
in CDCl3 solution on Bruker Avance 500 spectrometer at 500.13
(1H) and 125.76 (13C) MHz using TMS as internal standard. DEPT
spectrum was recorded in a standard manner using only a ꢀ = 135
pulse program. The 2D-COSY, ge-HSQC and ge-HMBC spectra were
obtained by using the standard Bruker pulse programs. 31P{ H}
1
∗
NMR spectrum was recorded in CDCl3 solution on Bruker Avance
500 spectrometer at 202.46 (31P) MHz using H3PO4 as external
Corresponding author. Tel.: +91 431 2503636; fax: +91 431 2500133.
E-mail address: kar@nitt.edu (R. Karvembu).
1386-1425/$ – see front matter © 2010 Elsevier B.V. All rights reserved.
doi:10.1016/j.saa.2010.06.004

412
M. Muthu Tamizh et al. / Spectrochimica Acta Part A 77 (2010) 411–418
Fig. 1. 1H NMR spectrum.
Table 1
1H and 13C NMR data, and 1H–1H COSY, 1H–13C HSQC and 1H–13C HMBC correlations.
Carbon
number
Chemical shift (ppm)
1H–1H
COSY
1H–13
HSQC
(1J)
C
1H–13
C
HMBC
ıH
ıC
2J
3J
4J
C1
C2
C3
–
–
117.80
160.00
122.58b
–
–
H4
–
–
–
–
–
–
–
–
6.35 (1H, d,
J = 9.14 Hz)
6.89 (1H, dd,
J = 9.14, 3.15 Hz)
–
3.78 (3H, s)
6.84 (1H, d,
J = 2.84 Hz)
8.85 (1H, d,
J = 10.4 Hz).
–
122.58
160.00(C2)
117.80(C1), 149.62(C5)
112.27(C7)a, 153.63(C14)
C4
125.39b
H3
125.39
149.62(C5)
–
112.27(C7), 160.00(C2)
–
C5
C6
C7
149.62
55.94b
112.27b
–
–
–
–
–
–
–
–
55.94
112.27
149.62(C5)
125.39(C4), 153.63(C8), 160.00(C2)
149.62(C5)
117.80(C1)
C8
153.63b
–
153.63
112.17(C7), 149.89(C9), 160.00(C2)
–
C9
C10
149.89
–
H11
–
–
–
–
–
7.36 (1H, d,
J = 7.57 Hz)
128.61b
128.60
149.89(C9)
121.81(C11)
C11
C12
C13
6.93–7.04 (2H, m) 121.81b
126.46b
H10
H13
H12
121.81
126.46
114.76
128.60(C10)
114.76(C13)
143.90(C14)
114.76(C13), 149.89(C14)a
128.60(C10), 143.90(C14)a
126.46(C12)
143.9(C14)
149.89(C9)
7.70 (1H, d,
114.76b
149.89(C9), 121.81(C11)a
J = 8.20 Hz)
C14
Cq
–
–
143.90
129.13
129.50
–
–
–
–
–
–
–
–
–
–
Co
7.78–7.94 (6H, m) 134.71b
134.80b
Ho–Hm
134.71,
134.80
128.08,
128.16
130.53,
130.55
(128.09–128.17)–(Cm) (130.53–130.55)–(Cp), (134.71–134.80)–(Co) –
Cm
Cp
7.40–7.46 (6H, m) 128.08b,
128.16b
Hm–Ho,
Hm–Hp
Hp–Hm
(134.71–134.80)–(Cq) (129.13–129.53)–(Cq)
(128.09–128.17)–(Cm) (134.71–134.80)–(Co)
–
–
7.49 (3H, t,
J = 7.09 Hz)
130.53b,
130.55b
Cq = (C15, C21, C27); Co = (C16, C22, C28, C20, C26, C32); Cm = (C17, C23, C29, C19, C25, C21); Cp = C18, C24, C30. Ho = (H16, H22, H28, H20, H26, H32); Hm = (H17, H23, H29,
H19, H25, H21); Hp = (H18, H24, H30).
a
Weak signal.
b
13C resonances appeared in DEPT135.

M. Muthu Tamizh et al. / Spectrochimica Acta Part A 77 (2010) 411–418
413
Fig. 2. 1H–1H COSY NMR spectrum.
standard. Melting point was determined with Khora digital melting
point apparatus.
2.3. Determination and refinement of structure
Single crystals of Ni complex for X-ray diffraction studies were
grown at room temperature from a dichloromethane–ethanol solu-
tion by the diffusion of diethyl ether vapour. Diffraction data were
collected on a Bruker Axs Kappa ApexII CCD diffractometer using
graphite monochromated Mo K␣ radiation (ꢁ = 0.71073 Å). The
structures were solved by direct methods (SHELXS-97) [10] and
refined by full-matrix least-squares fitting based on F2 using the
program SHELXL-97 [11]. All non-hydrogen atoms were refined
with anisotropic displacement parameters. All H atoms were
located by difference Fourier syntheses and were then included
in the refinement with idealized geometry riding on the atoms to
which they were bonded.
2.4. Synthesis of Ni(II) complex
The complex was prepared by stirring an ethanolic solu-
tion (10 cm3) of [NiCl2(PPh3)2] (0.5 g, 0.764 mmol) with
dichloromethane solution (10 cm3) of ligand (0.198 g, 0.764 mmol)
for 2 h at 25–27 ◦C. The resulting dark brown solutions were
concentrated to approximately 3 cm3 and cooled. Hexane (20 cm3)
Scheme 1. Structure of Ni(II) complex (numbering is given for better understanding
of discussions).

414
M. Muthu Tamizh et al. / Spectrochimica Acta Part A 77 (2010) 411–418
Fig. 3. HSQC NMR spectrum.
143.90,149.62, 149.89, 153.63, 160.00 ppm. 13C-DEPT 135 NMR
(125.76 MHz, CDCl3, 25 ◦C): 55.94, 112.22, 114.76, 121.83, 122.61,
125.39, 126.48, 128.09, 128.17, 128.62, 130.54, 130.56, 134.72,
134.80, 153.63 ppm.
was then added whereupon the product complex separated. The
brown coloured complex was filtered, washed with ethanol and
then with hexane and dried in vacuo. The formation of complex
was checked by TLC. Yield: 274 mg (62%). Decomposition tem-
perature 230 ◦C. Anal. Found: C, 66.46; H, 4.53; N, 2.42; S, 5.54.
Calc. for C31H24NNiOPS: C, 66.90; H, 4.41; N, 2.55; S, 5.95%. UV–vis
(CH3CN) ꢁmax (nm) (ε (dm3 mol−1 cm−1)): 213 (4708), 255 (3638),
273 (3716), 444 (863), 507 (209). IR (KBr disk), cm−1: ␯(C N)
1591, ␯(C O) 1358, ␯(C S) 750, ␯(Ni O) 533, ␯(Ni N) 461, bands
due to PPh3 1435, 1096, 692. 1H NMR (500 MHz, CDCl3, 25 ◦C):
ı = 3.78 (3H, s), 6.35 (1H, d, J = 9.14 Hz), 6.84 (1H, d, J = 2.84 Hz)
6.89 (1H, dd, J = 9.14, 3.15 Hz), 6.93–7.04 (2H, m), 7.36 (1H, d,
J = 7.57 Hz), 7.41–7.45 (6H, m), 7.49 (3H, t, J = 7.09 Hz), 7.70 (1H, d,
3. Results and discussion
The reaction of equimolar ratios of the ligand (H2L) and
[NiCl2(PPh3)2] yielded the new brown coloured complex of the gen-
eral formula [Ni(L)(PPh3)] [L = dianionic N-(2-mercaptophenyl)-4-
methoxysalicylideneimine] in good yield. It was found to be soluble
in CH2Cl2, CH3CN, C6H6, DMSO, DMF and C2H5OH. The analyti-
cal data for the complexes are in good agreement with the above
molecular formula. In the reaction, it has been observed that the
Schiff base behaves as a bifunctional tridentate ligand by substitut-
ing one of the triphenylphosphines and both the chloride ions from
the starting complex.
1
J = 8.20 Hz), 7.78–7.94 (6H, m), 8.85 (1H, d, J = 10.40 Hz). 31P{ H}
1
NMR (202.46 MHz, CDCl3, 25 ◦C), ı (ppm): 22.7 (s). 13C{ H}
NMR (125.76 MHz, CDCl3, 25 ◦C): 55.94, 76.77, 77.03, 77.28,
112.27, 114.76, 117.80, 121.81, 122.58, 125.39, 126.46, 128.08,
128.16, 128.61, 129.13, 129.50, 130.53, 130.55, 134.71, 134.80,

M. Muthu Tamizh et al. / Spectrochimica Acta Part A 77 (2010) 411–418
415
Fig. 4. HMBC NMR spectrum.
3.1. UV–vis and IR spectra
suggesting the coordination of phenolic oxygen to nickel ion [12].
A weak band observed at 756 cm−1 corresponding to ␯(C S) in the
ligands, shifts to lower wave number which supports sulfur coordi-
nation with the nickel centre [13]. The bands at 533 and 461 cm−1
in the complex are assigned to ␯(Ni O) and ␯(Ni N) respectively
[14]. Bands due to triphenylphosphine are also appearing in the
expected region [15].
The electronic spectrum of complex in CH3CN showed four
bands in the region 213–507 nm. The bands appearing in the region
213–273 nm have been assigned to intraligand transitions. A less
intense band at 444 nm corresponds to forbidden d → d transition.
The same behaviour has been observed in the electronic spectra of
other similar square planar nickel(II) complexes [12].
The spectrum of ligand exhibits a strong band at 1622 cm−1
,
3.2. 1D and 2D NMR spectra
which is assigned to ␯(C N) vibration. As a result of coordination,
this band shifts to lower wave number by ca. 30 cm−1 in complex
[12]. A band at 1358 cm−1 which is assigned to phenolic ␯(C O) in
the free ligand, is shifted to higher wave number in the complex
In 1H NMR spectrum of complex (Fig. 1), five doublets were
observed at ıH = 6.35 (1H, d, J = 9.14 Hz), ıH = 6.84 (1H, d, J = 2.84 Hz),
ıH = 7.36 (1H, d, J = 7.57 Hz), ıH = 7.70 (1H, d, J = 8.20 Hz) and

416
M. Muthu Tamizh et al. / Spectrochimica Acta Part A 77 (2010) 411–418
Fig. 5. Stack plot of 13C and DEPT 135 NMR spectrum.
ıH = 8.85 (1H, d, J = 10.40 Hz) which has been assigned to H3, H7,
H10, H13 and H8 (azomethine proton) respectively. The J value
of azomethine proton indicates that two aromatic units of Schiff
base are trans to each other [16]. A doublet of doublet observed
at ıH = 6.89 ppm (1H, dd, J = 9.14, 3.15 Hz) in the complex has been
assigned to H4. Complex exhibits a singlet at 3.78 ppm with three
proton count, corresponds to methoxy protons (H6). In the 13C
NMR spectra of the complex, methoxy (C6) and azomethine (C7)
carbon resonances observed at 55.94 and 153.63 ppm respectively.
1H–1H COSY spectrum (Fig. 2) displayed scalar couplings for adja-
cent protons like H3 ↔ H4, H10 ↔ H11 and H12 ↔ H13. Further,
the connection between these nine protons and its parent car-
bons namely C3 (ıC 122.58), C7 (ıC 112.27), C10 (ıC 128.61), C13
(ıC 114.76), C8 (ıC 153.61), C4 (ıC 125.39) and C6 (ıC 55.94) is
confirmed by direct couplings in HSQC spectrum (Fig. 3). A quin-
tet shaped multiplet observed in the 6.93–7.04 ppm region with a
proton count of two is assigned to H11 and H12. This multiplet
shows scalar couplings with H10 (ıH = 7.36) and H13 (ıH = 7.70)
in its 1H–1H COSY spectrum. It is difficult to find out coupling
for H11 ↔ H12 due to merged resonances. The connection of H11
and H12 with its parent carbon atoms, C11 (ıC 121.81) and C12
(ıC 126.46), is established by HSQC spectrum. Nickel(II) complex
exhibits three multiplets in the regions of ıH 7.41–7.45 (6H, m), ıH
7.49 (3H, m) and ıH 7.78–7.94 (6H, m) which has been assigned to
meta, para and ortho protons respectively, of three phenyl rings
of triphenylphosphine. This assignment is based on scalar cou-
plings in 1H–1H COSY spectrum, which shows correlation only
between Ho ↔ Hm and Hp ↔ Hm [Ho = (H16, H22, H28, H20, H26,
H32); Hm = (H17, H23, H29, H19, H25, H21); Hp = (H18, H24, H30)].
The absence of resonances due to phenolic and thiolato hydrogen
indicates the deprotonation of these groups and the Schiff base
behaves as dianionic ligands. The 13C NMR resonances for C14 S1,
C5 O2, C9 N1 and C2 O1 are observed at 143.90, 149.62, 149.89
and 160.01 ppm respectively [17,18]. It is interesting that HMBC
spectrum (Fig. 4) was very much useful to distinguish the reso-
nances due to C5 (ıC 149.62) and C9 (ıC 149.89). The DEPT 135
spectrum shows disappearance of resonances at 117.80, 129.13,
129.50, 143.90, 149.62, 149.89, and 160.01 ppm. The 13C resonances
at 129.13 and 129.50 are assigned to quaternary carbons present in
triphenylphosphine. This indicates that three quaternary carbons
arising from aromatic units of triphenylphosphine are in two dif-
Fig. 6. 31P NMR spectrum.
ferent magnetic environments. Stack plot of 13C and DEPT 135 NMR
spectrum is depicted in Fig. 5. 31P NMR spectrum (Fig. 6) of the com-
plex exhibits a singlet at 22.72 ppm suggesting the presence of one
coordinated triphenylphosphine in nickel(II) complex [7]. In HMBC
correlation spectrum, methoxy protons (H6, ıH 3.78 (3H, s)) show
a strong three bond coupling with C5 (ıC 149.62) which was a rare
observation as coupling occurs through an oxygen atom. In addi-
tion, the coupling of imine proton (ıH 8.89) with three quaternary
carbons, viz. C1 (ıC 117.80), C2 (ıC 160.00), C9 (ıC 149.89) and C7
(ıC 112.17) has been understood from HMBC correlation spectrum.
1H and 13C NMR data, and 1H–1H COSY, 1H–13C HSQC and 1H–13
HMBC correlations are given in Table 1.
C
3.3. X-ray crystallography
ORTEPIII view [19] of structure of complex is shown in Fig. 7.
The nickel atom in this complex has approximate square pla-
nar coordination with S1, N1, O1 of Schiff base and P1 of
triphenylphosphine with the metal atom having maximum devi-
ation of 0.029(5) Å from the mean plane. Table 2 shows crystal
data, data collection and structure refinement parameters. The
bond angles O1 Ni1 S1, N1 Ni1 P1, O1 Ni1 P1, O1 Ni1 N1,
N1 Ni1 S1 and S1 Ni1 P1 are 175.08(3)◦, 177.17(5)◦, 85.22(4)◦,
94.96(6)◦, 89.72(5)◦ and 90.03(19)◦ respectively. The Ni1 P1,
Ni1 O1, Ni1 N1 and Ni1 S1 bond distances are in the usual range
[12]. Table 3 shows selected bond lengths and bond angles. The

M. Muthu Tamizh et al. / Spectrochimica Acta Part A 77 (2010) 411–418
417
Table 3
Selected bond lengths (Å) and angles (◦).
Bond lengths (Å)
Bond angles (◦)
Ni1 O1
Ni1 N1
Ni1 S1
Ni1 P1
S1 C14
P1 C15
P1 C21
P1 C27
O1 C2
N1 C8
N1 C9
C1 C2
C1 C8
C9 C14
C5 O2
O2 C6
1.8461(13)
1.9028(15)
2.1297(5)
2.1875(5)
1.7481(19)
1.8276(17)
1.8132(19)
1.8142(19)
1.307(3)
1.298(15)
1.430(14)
1.405(3)
1.415(3)
1.389(3)
O1 Ni1 N1
O1 Ni1 S1
N1 Ni1 S1
O1 Ni1 P1
N1 Ni1 P1
S1 Ni1 P1
C14 S1 Ni1
C27 P1 C21
C27 P1 C15
C21 P1 C15
C27 P1 Ni1
C21 P1 Ni1
C15 P1 Ni1
C8 N1 C9
C8 N1 Ni1
C9 N1 Ni1
C2 O1 Ni1
N1 C8 C1
C2 C1 C8
94.96(6)
175.08(3)
89.72(5)
85.22(4)
177.17(5)
90.03(19)
98.23(6)
107.60(9)
102.41(8)
105.04(8)
116.57(6)
104.66(6)
119.61(6)
119.31(16)
122.95(13)
117.57(11)
126.12(13)
126.87(18)
122.13(18)
118.66(14)
114.90(19)
125.4(2)
1.375(2)
1.410(3)
C9 C14 S1
C7 C5 O2
O2 C5 C4
C5 O2 C6
116.75(18)
Fig. 7. Molecular structure of complex showing 50% displacement ellipsoids.
Table 2
Crystal data, data collection and structure refinement parameters.
Parameters
[Ni(L)(PPh3)]
Empirical formula
Formula weight
Colour
C32H26NNiO2PS
578.28
Black
Habit
Block
Crystal dimension
Crystal system
Space group
a (Å)
0.25 mm × 0.20 mm × 0.20 mm
Monoclinic
P21/c
13.1300(5)
b (Å)
17.3071(6)
c (Å)
12.4713(5)
90
104.5210(10)
90(1)
2743.48(18)
4
˛ (◦)
ˇ (◦)
ꢂ (◦)
Volume (Å3)
Z
Temperature
DC (Mg/m3)
Absorption coefficient (mm−1
F (0 0 0)
293(2) K
1.400
0.872
1200
Fig. 8. Schematic drawing of the crystal packing showing C H· · ·␲ interactions. The
)
hydrogen atoms except those involved in interactions are omitted for clarity.
ꢁ (Mo K␣) (Å)
0.71073
1.6–28.7
 range (◦)
Scan type
␻, ␸
Index ranges
Reflections collected/unique
Rint
Refinement method
Diffractometer
Absorption correction
−17 ≤ h ≤ 17, −23 ≤ k ≤ 21, −16 ≤ l ≤ 14
rings of the triphenylphosphine and the mean plane of Schiff
base are 39.85(7)◦ (C27. . .C32), 86.00(5)◦ (C21. . .C26), 88.11(5)◦
(C15. . .C20) showing their asymmetric orientation with respect to
Schiff base which is in agreement with the 13C NMR data which
reveal that two of the phenyl rings of triphenylphosphine are
almost chemically similar and other one is different.
33535/7081
0.0300
Full-matrix least-squares on F2
Bruker axs kappa APEX2 CCD
Multi-scan SADABS
0.0326/0.0841
0.0510/0.0992
1.079
Final R indices R1/wR2 [I > 2ꢃ(I)]
R1/wR2 (all data)
Goodness-of-fit on F2
ꢄ
and ꢄ
(eÅ−3
)
0.30 and −0.26
max
min
Data/restraints/parameters
7081/0/344
4. Conclusion
Mononuclear Ni(II) complex of the type [Ni(L)(PPh3)] [H2L = N-
(2-mercaptophenyl)-4-methoxysalicylideneimine] was prepared
and characterized by 2D NMR, IR and electronic spectroscopy.
Structure of the complex was determined by X-ray crystallogra-
phy, which is stabilized by various strong C H· · ·␲ interactions.
13C NMR and X-ray crystal structure of complex reveal that two
of the phenyl rings of triphenylphosphine are almost chemically
similar and other one is different which was supported by 2D NMR
studies.
Schiff base moiety of the complex is not planar with dihedral angle
between aminothiophenol moiety and 5-methoxysalicylidene
moiety being 16.72(6) Å. The phenyl ring (C21. . .C26) form fairly
strong C H· · ·␲ contacts with H6b $1 (2.586(12) Å, symm $1: 1 − x,
−y, −z), H13 $2 (2.794(3) Å, symm $2: 2 − x, −y, 1 − z) and H32 $3
(2.619(3) Å, symm $3: x, −1/2 − y, −1/2 + z) to form a three dimen-
sional network. Packing diagram (Fig. 8) was produced using the
program MERCURY [20]. The dihedral angles between phenyl

418
M. Muthu Tamizh et al. / Spectrochimica Acta Part A 77 (2010) 411–418
Supplementary data
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data of the complex. These data can be obtained free of charge
via www.ccdc.ac.uk/conts/retrieving.html, or from the Cambridge
Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ,
UK; fax: +44 1223 336 033; or e-mail: deposit@ccdc.cam.ac.uk.
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II] for financial support and Director, NITT for providing research
scholar seed money. R.K. thanks STEC, Sophia University, Japan for
visiting fellowship. We also thank SAIF, IIT-Madras for crystal struc-
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Appendix A. Supplementary data
Supplementary data associated with this article can be found, in
the online version, at doi:10.1016/j.saa.2010.06.004.
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