Crystal structure, spectroscopic properties and DFT studies on copper (II) complex of bis{(E)-1-[(2-phenoxyphenylimino)methyl]naphthalene-2-ol}chloroform solvate

Article abstract of DOI:10.1016/j.molstruc.2014.05.025

Copper (II) complex of the title Schiff base compound was synthesized from the reaction of 2-hydroxy-1-naphthaldehyde with 2-phenoxyaniline. The complex has been characterized by FT-IR, and X-ray single-crystal techniques. The molecular geometry, vibratio

Full text of DOI:10.1016/j.molstruc.2014.05.025

Accepted Manuscript
Crystal structure, spectroscopic properties and DFT studies on copper(II) com-
plex of bis{(E)-1-[(2-phenoxyphenylimino)methyl]naphthalene-2-ol}chloro-
form solvate
Mustafa Macit, Gökhan Alpaslan
PII:
S0022-2860(14)00511-0
DOI:
http://dx.doi.org/10.1016/j.molstruc.2014.05.025
MOLSTR 20624
Reference:
Journal of Molecular Structure
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Received Date:
Revised Date:
Accepted Date:
31 January 2014
6 March 2014
12 May 2014
Please cite this article as: M. Macit, G. Alpaslan, Crystal structure, spectroscopic properties and DFT studies on
copper(II) complex of bis{(E)-1-[(2-phenoxyphenylimino)methyl]naphthalene-2-ol}chloroform solvate, Journal of
Molecular Structure (2014), doi: http://dx.doi.org/10.1016/j.molstruc.2014.05.025
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Crystal structure, spectroscopic properties and DFT studies on copper(II) complex of
bis{(E)-1-[(2-phenoxyphenylimino)methyl]naphthalene-2-ol}chloroform solvate
Mustafa Macita, Gökhan Alpaslanb*
aDepartment of Chemistry, Faculty of Arts & Science, Ondokuz Mayıs University, 55139,
Samsun, Turkey
bDepartment of Medical Services and Techniques, Vocational High School of Health
Services, Giresun University, 28200, Giresun, Turkey
Abstract
Copper (II) complex of the title Schiff base compound was synthesized from the
reaction of 2-hydroxy-1-naphthaldehyde with 2-phenoxyaniline. The complex has been
characterized by FT-IR, and X-ray single-crystal techniques. The molecular geometry,
vibrational frequencies values of the compound in the ground state have been calculated using
the density functional theory (DFT/B3LYP) method with the LANL2DZ basis set and
compared with the experimental data. The calculated results show that the optimized
geometry is compatible with the crystal structure and the theoretical vibrational frequencies
are in good agreement with the experimental values. The energetic behavior of the compound
in solvent media has been examined using B3LYP method with the LANL2DZ basis set by
applying the polarizable continuum model (PCM). In addition, frontier molecular orbital
analysis (HOMO-LUMO), natural bond orbital analysis (NBO) and non-linear optical (NLO)
properties of the compound were investigated using same theoretical calculations.
Keywords: Schiff base complex · X-ray · FT-IR · DFT · Non-linear optic
*Corresponding author. Tel : +904543101000
E-mail : gokhan.alpaslan@giresun.edu.tr

1. Introduction
Schiff bases compounds have been widely used due to their potential applications in
many fields, such as photochromic and thermochromic properties [1], proton transfer
tautomeric equilibria [2], biological and pharmacological activities [3–6]. They may have
interesting chemical properties, depending on the substituents with different electron-donating
or electron-withdrawing groups [7]. This cause their non-linear properties have an importance
for the design of various molecular electronic devices such as optical switches and optical
data storage devices [8,9]. Schiff base compounds have often been used as chelating ligands
in the field coordination chemistry [10]. These properties have resulted in wide applications in
the biological field [10,11]. Copper (II) complexes are known to be effective against
rheumatoid arthritis and they also show anti-ulcer activity [12]. In additional, some copper
(II) complexes with Schiff base possess antifungal, antibacterial, and anticancer properties
[13–15].
In recently years, theoretical calculation methods are used to describe the molecular
structures and spectroscopic properties as well as experimental studies. Density functional
theory (DFT) which is one of these methods have been widely used in literature because of its
great accuracy in reproducing the experimental values in molecule geometry, vibrational
frequencies, atomic charges, dipole moment, electronic properties etc [16-19].
In previous work ligand (E)-1-((2-phenoxyphenylimino)methyl)naphthalen-2-ol
molecule was synthesized and characterized by X-ray single diffraction [20]. In this study, we
present
the
synthesis
and
structural
behavior
of
bis{(E)-1-[(2-
phenoxyphenylimino)methyl]naphthalene-2-ol}Cu(II) chloroform solvate obtained by
reaction of (E)-1-((2-phenoxyphenylimino)methyl)naphthalen-2-ol with Cu(CO2CH3)2.H2O.
The aim of this study is to investigate molecular structure and vibrational frequencies of the
title compound, both experimentally and theoretically. The properties of the structural

geometry, natural bond orbital (NBO) analysis, frontier molecular orbitals (FMOs), and
nonlinear optical (NLO) properties for the compound at the DFT/B3LYP/LANL2DZ level
were studied.
2. Experimental and computational method
2.1. Physical measurement
The FT- IR spectrum of the title compound was recorded in the 4000- 400 cm-1 region
with a Shimadzu FTIR-8900 spectrophotometer using KBr pellet. X-ray single crystal
structure was determined on a STOE IPDS II diffractometer.
2.2. Synthesis of (E)-1-[(2-phenoxyphenylimino)methyl]naphthalen-2-ol
(E)-1-((2-phenoxyphenylimino)methyl)naphthalen-2-ol was synthesized according to
the literature method [20]. (E)-1-((2-phenoxyphenylimino)methyl)naphthalen-2-ol was
prepared by refluxing a mixture of a solution containing 2-hydroxy-1-naphthaldehyde (17,2
mg, 0,1 mmol) in ethanol (30 ml) and a solution containing 2-phenoxyaniline (18,5 mg, 0,1
mmol) in ethanol (20 ml). The reaction mixture was stirred for 2 hour under reflux. Crystals
of the title compound were obtained by slow evaporation of an ethanol solution (Yield 68%;
m.p. 411-413 K).
2.3. Synthesis of bis{(E)-1-[(2-phenoxyphenylimino)methyl]naphthalene-2-ol}Cu(II)
Cu(II) complex was prepared by refluxing a mixture of a solution containing (E)-1-((2
phenoxyphenylimino)methyl)naphthalen-2-ol (67,8 mg, 0,2 mmol) in ethanol (30 ml) and a
solution containing Cu(CO2CH3)2.H2O (19,9 mg, 0,1 mmol) in ethanol (20 ml). The reaction
mixture was stirred for 4 hour under reflux. Single crystals of the title compound for X-ray
analysis were obtained by slow evaporation of an chloroform-propanol mixture solution
(64%, mp:470-473 K, Scheme 1).

Scheme 1. The chemical diagram of bis{(E)-1-[(2-phenoxyphenylimino)methyl]naphthalene-
2-ol}Cu(II) chloroform solvate.
2.3. X-ray crystallography
Data collection was done at 298 K on a STOE IPDS II diffractometer by the w scan
technique using graphite monochromated MoK radiation (λ=0.71073 Å). Cell refinement was
α
performed using X-AREA software [21]. Absorption correction (µ = 0.79 mm-1) was
obtained by the integration method via X-RED32 software [21]. The crystal structure was
solved by direct methods using SHELXS–97 [22]. The scattering factors were taken from
SHELXL-97 [22]. The molecular graphics were done using Ortep-3 for Windows [23]. The
data collection conditions and parameters of refinement process are listed in Table 1.
2.4. Theoretical methods
All theoretical computations were done by using Gaussian 03 W program package
[24]. For calculation of molecule geometry was created using the atomic coordinates obtained
from X-ray geometry. Geometry optimization of the molecule was performed by using DFT
method with Becke’s three parameters hybrid exchange-correlation functional (B3LYP) [25]
at LANL2DZ basis set [26-28]. The harmonic vibrational frequencies were calculated at the
same level of theory for the optimized structure and the obtained frequencies were scaled by

0.9611 [29]. The assignments of vibrational bands have been made by using Gauss-View
molecular visualization program [30]. The energetic and dipole moments behavior in solvent
media of the title compound were carried out by using PCM method [31–34]. The linear
polarizability and first hyperpolarizability properties of the compound were obtained from
molecular polarizabilities based on theoretical calculations. In addition, NBO analysis was
performed at B3LYP/LANL2DZ level by means of the NBO 3.1 program within the Gaussian
03 W package [35].
Table 1
Crystal data and refinement for the title compound.
Chemical formula
Crystal shape/color
Formula weight
Crystal system
C46H32CuN2O4⋅CHCl3
Prism/Black
859.64
Monoclinic
P21/c
Space group
Unit cell parameters
a = 13.7884(5) Å
b = 16.1674(8) Å
c = 20.9582(8) Å
β= 120.812(2)o
4012.6(3) Å3
4
1.423
0.79
1764
0.78×0.61×0.33
Volume
Z
Dx (Mg cm-3)
μ(mm-1)
F000
Crystal size (mm3)
Data collection
Diffractometer/meas.meth
Absorption correction
Tmin
STOE IPDS II/w-scan
Integration
0.632
Tmax
0.804
No. of measured, independent 18071, 7808, 5040
and observed reflections
Criterion for observed
I > 2σ(I)
reflections
Rint
0.043
26.0
θ
max
Refinement
Refinement on
F2
R[F2 > 2σ (F2)], wR, S
No. of reflection
No. of parameters
Weighting scheme
0.046, 0.125, 0.92
7808
546
w=1/[σ (F0 )+(0.074P)2 +
2
2
0.2501 P] P=( F0 +2Fc2)/3
2
∆ρmax, ∆ρmin (e Å-3)
0.59, -0.40

3. Results and discussion
3.1. Crystal description
The title complex, an Ortep-3 view of which is shown in Fig.1, crystallizes in the
monoclinic space group P21/c with Z = 4 in the unit cell. The complex contains two (E)-1-
[(2-phenoxyphenylimino)methyl]naphthalen-2-ol ligands with a Cu(II) metal atom and a
solvate chloroform molecule. The metal center is distorted square-planar which is supported
by the cis-N2O2 donor atoms of the coordinated Schiff base ligands. The N-Cu-O trans
angles are 155.04(10)° and 152.53(10)°, indicating a distortion of the square-planar
coordination. However, the O–Cu–O and N–Cu–N cis angle are 88.95(8)° and 98.89(10)°,
respectively. The maximum deviation is 0.4599 (14) Å for atom O3 in the square-planar
coordination (Cu1, N1, N2, O1, O3). In addition, the deviations for Cu1, N1, N2 and O1
atoms in the square-planar coordination are -0.0162 (9), 0.4034 (11), -0.3938 (11), and -
0.4532 (14) Å, respectively, from the mean plane through these five atoms. The dihedral
angle between coordination plane with six-membered chelating plane A[O1,N1,C1,C2,C11] is
21.70°, while the dihedral angle between the one and the other chelating plane
B[O3,N2,C24,C25,C34] is 24.88°. Just as the Cu–O1 and Cu–O3 bond lengths are 1.905 (2)
and 1.904 (2) Å, the Cu–N1 and Cu–N2 bond lengths are 1.962 (3) and 1.961 (2) Å,
respectively. The Cu–N and Cu–O values in the title compound agree with those in other
naphthalene complexes. In the literature, the Cu–N have values between 1.870 and 1.920 Å,
while the Cu–O bond lengths are range from 1.970 to 2.010 Å [36-40]. The Cl atoms of
chloroform molecule are disordered over two positions with site occupancies of 0.684(7) and
0.316(7). The complex molecules are linked via solvent chloroform molecules by C–H···O
hydrogen bonds. In addition, there is a C–H···πinteraction of C45–H45 and the phenyl ring.

Perpendicular distance between atom H45 and the plane of the phenyl ring is 2.88 Å (Fig. 2).
The details of the hydrogen bonds are summarized in Table 2.
Fig. 1. a) Ortep-3 diagram of the title compound. Displacement ellipsoids are drawn at the
30% probability level. The intramolecular hydrogen bond is shown as a dashed line. b) The

theoretical geometric structure of the title compound (at B3LYP/LANL2DZ level). H atoms
are omitted for the sake of clarity.
Fig. 2. A partial packing diagram for the title compound, with C–H···πinteractions.
Table 2
ο
Hydrogen-bond geometry (Å, ).
D–H···A
D–H
H···A
2.26 (5)
2.88
D···A
D–H···A
156 (4)
164
C47–H47···O1
C45–H45···Cg8i
0.97 (5)
0.93
3.174 (5)
3.786 (6)
Symmetry code (i) : x-1, 1/2-y, z-1/2.
(Cg8 is the centroids of the C18-C23 ring).
3.2. Theoretical structure
Geometric optimization of investigated compound was performed by using
DFT/B3LYP method with LANL2DZ basis set (Fig. 1b). The some bond lengths, bond angles
and torsion angles of the optimized structure are listed in Table S1 (Supplementary
Information) and compared with the experimental data of the compound. As can be seen from
Table S1 (Supplementary Information), most of molecular geometric parameters are slightly
different from the experimental ones. According to crystallographic studies, the dihedral angle
between the coordination plane and chelating plane [A] is 21.70°, while this angle has been

calculated at 37.42° for optimized structure. In additional, the N–Cu–O trans angles are
calculated 155.04(10)° and 152.53(10)°, as well as the O–Cu–O and N–Cu–N cis angle are
found 88.95(8)° and 98.89(10)°, respectively. The Cu–O1, Cu–O3, Cu–N1 and Cu–N2 bond
lengths obtained by B3LYP differ by 0.047, 0.045, 0.048 and 0.046 Å, respectively, from the
experimental results. The biggest differences between experimental and calculated bond
lengths and angles as 0.068 Å in C20–C21 bond and are 5.47° in O3–Cu1–N1 angle,
respectively. In order to compare the theoretical results with the experimental values, root
mean square error (RMSE) is used. The calculated RMSE for bond lengths and bond angles
are 0.032 Å and 1.21°, respectively. It is well known that the experimental results in the solid
state are related to molecular packing, but the theoretical results are related to the gas phase of
the isolated molecules. According to these results, it is seen that the B3LYP calculation well
reproduce the geometry of the compound.
3.3. Vibrational analysis
FT-IR spectrum of the investigated compound was measured in the 4000-400 cm-1
region using KBr pellet on a Shimadzu FT-IR 8900 spectrophotometer (Fig. 3). FT-IR spectra
of compounds derived from 2-hydroxy-1-naphthaldehyde Schiff bases have some
characteristic stretching bands (CH, CN, CO). The vibrational frequencies of the compound
were calculated by using B3LYP/LANL2DZ method. Determinations of the calculated
vibrational bands have been made by using Gauss-View molecular visualization program. The
assignments of the observed vibration bands have been performed and compared with the
calculated frequencies. The experimental and calculated vibrational frequencies, and their
assignments are given in Table S2 (Supplementary Information). Because of the states such
as negligence of anharmonicity, incomplete inclusion of electron correlation effects and basis
set deficiencies, the calculated harmonic vibrational frequencies become bigger than the

observed ones [41, 42]. For this reason, the calculated wavenumbers are usually scaled by
scaling factor to compare with observed wavenumbers and at the present work, the scaling
factor are taken as 0.9611 for B3LYP/LANL2DZ level [29].
The aromatic C–H stretching, C–H in-plane bending and C–H out-of-plane bending
vibrations appear in 2900–3100 cm−1, 1000–1500 cm−1 and 700–1000 cm−1 frequency ranges,
respectively [43]. The C–H stretching bands for phenyl rings have been observed at 3056
cm−1, while ones for naphthalene rings are found 2964, 3010 and 3032 cm−1. The C–H in-
plane bending vibrations are observed at the interval 1037–1578 cm−1 as the combined with
other bands. Similarly, the C–H out-of-plane bending vibrations are found between 691–983
cm−1 and they are usually observed as strong bands. The CC stretching modes in aromatic
rings can occur between 1600–1400 cm−1 in fingerprint region [44]. The observed bands at
1603, 1578, 1536, 1508, 1484, 1453, 1429, 1396, 1363, 1309, 1275, 1242, 1211 and 1037
cm−1 as combined with other vibrations modes can attribute to CC stretching modes of phenyl
and naphthalene rings. Additionally, the CCC in-plane bending modes of phenyl rings are
observed at 562 and 853 cm−1. The observed bands at 416, 460 and 477 cm−1 can be assigned
to CCCC out of plane bending modes of aromatic rings. The CO stretching bands are
observed at 1242 and 1396 cm−1, while NC ones are found at 1179 and 1536 cm−1. The Cu–N
and Cu–O stretching modes for copper (Cu) atom the coordinated with nitrogen (N) and
oxygen (O) atoms are observed at 536 and 501 cm−1, respectively. These results are in
agreement with the literature [40, 45].
The correlation graphics between the calculated and experimental IR vibrational
frequencies of the compound is presented in Fig. 4 and correlation coefficient is obtained as
0.9997. As we can see from the correlation graph in Fig. 4, the experimental values are in a
good agreement with the calculation ones.

Fig. 3. FT-IR spectrum of the title complex.
Fig. 4. Correlation graph of calculated and experimental frequencies of the title compound
3.4. Frontier molecular orbitals (FMOs)
The highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular
orbital (LUMO) are named as frontier molecular orbitals (FMOs). The FMO are very

important in determining molecular properties such as electric, optic, and chemical reactions
[46]. The distributions and energy levels of the α (spin-up) and β (spin-down) frontier
molecular orbitals (FMOs) were computed at B3LYP/LANL2DZ level for the compound and
are shown in Fig. 5. The value of the energy gap of the compound between the HOMO and
LUMO is 3.249 eV for α(spin-up) orbitals and 2.645 eV for β(spin-down) orbitals. These
energy gaps are in agreement with the value of 2-3 eV often encountered for stable transition
metal complexes [47, 48].
3.5. Total energies in solvent media
In order to evaluate the energetic behavior of the compound in solvent media, we
carried out calculations in gas phase and three kinds of solvent ( = 4.9, chloroform;
=
24.55, ethanol; = 78.39, water). The calculated total and dipole moment using the PCM by
B3LYP/LANL2DZ are listed in Table 3. From Table 3, we can conclude that the total
molecular energies obtained by PCM method decrease with the increasing polarity of the
solvent, while the dipole moments will increase with the increase of the polarity of the
solvent. According to these results, the stability of the title compound increases in going from
the gas phase to the solution phase.
Table 3
Total energies and dipole moments of the title compound in different solvents.
Method
Energy (a.u)
ε
ΔE (kcal/mol)
μ(Debye)
LANL2DZ
1
-2461.98070571
7.9073
PCM
4.9
-2462.00379379 -14.4877
-2462.01498787 -21.5120
-2462.01979672 -24.5296
10.0484
11.1274
11.6104
24.55
78.39

Fig. 5. Molecular orbital surfaces and energy levels given in parantheses for the α(spin-up)
and β(spin-down) HOMO−LUMO of the title compound computed at B3LYP/LANL2DZ
level.

3.6. NBO analysis
Natural bond orbital analysis method provides important information about the
electronic structure of the metal complexes [49]. The NBO analysis of the compound was
calculated by using B3LYP/LANL2DZ method (Table 4). According to the NBO analysis,
the electron number of 3d, 4s and 4p orbits of Cu are 9.31, 0.27 and 0.35, respectively as well
as the electron number of 2s and 2p orbits of N1 are 1.34 and 4.24 and the electron number
of 2s and 2p orbits of N2 are 1.35 and 4.25, respectively. Similarly, the electron number of 2s
of the O1 and O3 atoms are 1.69 while one of 2p of the O1 and O3 atoms are 5.04 and 5.02,
respectively. According to these results, we can deduced that 3d, 4s and 4p orbits of the Cu
atom coordinate with N1, N2, O1 and O3 atoms. Similarly, coordination with copper atom of
nitrogen and oxygen atoms are formed by using their 2s and 2p orbits. In additional, the
Natural Population Analysis (NPA) atomic charge distributions on the atoms of the title
complex were calculated by B3LYP method using the LANL2DZ basis set. The calculated
natural charge on the Cu atom in the title complex is + 1.06. The obtained result show that
charge transfer realized from the ligands to the Cu (II) ion. The largest negative charges are
located on the oxygen atoms O1 (-0.73) and O3 (-0.72) for copper (II) complex.
Table 4
Selected natural atomic charges and electronic configurations for title complex.
Atoms
Cu
Net Charge Electronic Configuration
1.06
[core]4s(0.27)3d(9.31)4p(0.35)5p(0.01)
N2
-0.60
-0.61
-0.73
-0.72
[core]2s(1.34)2p(4.24)3p(0.02)
[core]2s(1.35)2p(4.25)3p(0.02)
[core]2s(1.69)2p(5.04)3p(0.01)
[core]2s(1.69)2p(5.02)3p(0.01)
N1
O1
O3

3.7. Non-linear optical effects
Non-linear optical (NLO) effects arise from the interactions of electromagnetic fields
in various media to produce new fields altered in phase, frequency, amplitude or other
propagation characteristics from the incident fields [50]. NLO is at the forefront of current
research because of its importance in providing the key functions of frequency shifting,
optical modulation, optical switching, optical logic, and optical memory for the emerging
technologies in areas such as telecommunications, signal processing, and optical
interconnections [51-54]. The total static dipole moment (μ), the linear polarizability (α) and
the first hyperpolarizability (β) using the x, y, z components are defined as [55, 56]:
μ = μx2 + μy2 + μz2
(2)
(3)
(4)
αxx +αyy +αzz
α =
3
2
2
2
(
)
(
)
(
)
β = βxxx + βxyy + βxzz + βyyy + βxxy + βyzz + βzzz + βxxz + βyyz
It is well known that the higher values of molecular polarizability and hyperpolarizability are
important for more active NLO properties. The polarizabilities and hyperpolarizability are
reported in terms of atomic units (a.u) and the calculated values have been converted by using
1 a.u3 = (0.529)3 Å3 for α and 1 a.u = 8.641x10-33 cm5/esu for β [57]. The Schiff base
compounds have been under investigation for several years because of their potential
application to optical communications and because many of them have NLO behavior [43,
58,59]. The effect of electron donor–acceptor substituents on the first hyperpolarizability of
conjugated systems has received a great deal attention in recent years [60]. To understand the
NLO properties of the title compound, the linear polarizability (α) and the first
hyperpolarizability (β) were calculated at the B3LYP/LANL2DZ level using Gaussian 03W

program package and the results obtained from calculation were given in Table 5. The
calculated polarizability (α) and first hyperpolarizability (β) for the compound are 67.504 Å3
and 12.051 x 10-30 cm5/esu, respectively. Urea is one of the essential molecules used for
determition of the NLO properties of molecular systems. Therefore, it is used as reference
molecule in NLO studies. The calculated αand βvalues with B3LYP/LANL2DZ method of
urea are 3.882 Å3 and 0.409 x 10-30 cm5/esu. The polarizability and first hyperpolarizability
for title molecule is approximately 17.3 and 29.4 times than those of urea. When it is
compared to the related Schiff base metal complex in the literature, the calculated value of β
of the compound is bigger than that of bis[2-hydroxy-κO-N-(2-pyridyl)-1-naphthaldiminato-κ
N]zinc(II) (β= 11.387 x 10-30 cm5/esu) [43]. These results indicate that title compound is a
good candidate of nonlinear optical material.
Table 5
Calculated polarizability and first hyperpolarizability components (a.u.) for the title
compound.
Parameters
Value (a.u)
Parameters
Value (a.u)
341.063192
825.4394472
α
xx
β
xxx
27.7710207
516.410009
19.9040715
-70.3999642
522.9993496
1368.342868
456.1142894
-775.8296823
-156.7744231
-100.2058864
619.3965722
149.922692
-54.973419
α
β
xy
xxy
α
xz
β
xyy
α
yy
β
yyy
α
yz
β
xxz
α
zz
β
yyz
α
total
β
xzz
-248.0151873
92.9380384
-10.4047554
Δα
β
yzz
β
zzz
β
0

4. Conclusion
In this study, C46H32CuN2O4⋅CHCl3 complex has been synthesized and characterized
by IR and X-ray single-crystal diffraction. The crystal structure of the complex is stabilized
by C–H···O hydrogen bond and C–H···πinteraction. In addition to the X-ray crystal structure,
the molecular geometry and vibrational frequencies of the title compound were calculated
using the density functional method (B3LYP) with the LANL2DZ basis set. The calculated
results show that the optimized geometries can well reproduce the crystal structure, and the
theoretical vibrational frequencies show good agreement with experimental values. The total
energy of the title compound decreases with increasing polarity of the solvent. The Natural
Population Analysis show that charge transfer occurred from the ligands to the Cu (II) ion.
This study also demonstrates that the title compound can be used as a good nonlinear optical
material.
Acknowledgment
We sincerely thank to Professor Dr Orhan Büyükgüngör for his help with the data collection.
Supplementary data
Crystallographic data for the structure reported in this article have been deposited with the
Cambridge Crystallographic Data Centre as supplementary publication number CCDC
951665. Copies of the data can be obtained free of charge on application to CCDC 12 Union
Road, Cambridge CB21 EZ, UK
(Fax: (+44) 1223 336-033; e-mail: data_request@ccdc.cam. ac.uk).

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Highlights
► The compound was characterized by IR and X-ray crystallography.
► Molecular geometry was determined by DFT method.
► The calculated results were compared with experimental results.
► NLO and NBO analysis of the compound were studied.