Acid nickel oxovanadate [Ni(H2O)6]2[H 2V10O28] ? 6H2O: Synthesis, IR spectra, thermal analysis, and crystal structure

Article abstract of DOI:10.1134/S1070328407080064

Acid nickel oxovanadate, [Ni(H₂O)₆] ₂[H₂V₁₀O₂₈] ? 6H₂O (I) was synthesized and studied by X-ray diffraction analysis, thermogravimetry, powder X-ray diffraction, and IR spectroscopy. The crystals are triclinic: space group P1 , a = 8.869(2) A, b = 10.869(2) A, c = 11.116(2) A, α = 65.14(3)°, β = 74.11(3)°, γ = 70.47(3)°, V = 907.41 A³, ρ(calcd.) = 2.56 g/cm ³, Z = 1.

Full text of DOI:10.1134/S1070328407080064

ISSN 1070-3284, Russian Journal of Coordination Chemistry, 2007, Vol. 33, No. 8, pp. 582–587. © Pleiades Publishing, Ltd., 2007.
Original Russian Text © G.Z. Kaziev, A.V. Oreshkina, S.H. Quinones, D.A. Alekseev, V.E. Zavodnik, T.Yu. Glazunova, 2007, published in Koordinatsionnaya Khimiya, 2007,
Vol. 33, No. 8, pp. 593–598.
Acid Nickel Oxovanadate [Ni(H O) ] [H V O ] · 6H O:
2
6 2
2
10 28
2
Synthesis, IR spectra, Thermal Analysis, and Crystal Structure
a
a
b
a
G. Z. Kaziev , A. V. Oreshkina , S. H. Quinones , D. A. Alekseev ,
c
d
V. E. Zavodnik , and T. Yu. Glazunova
a
Moscow State Pedagogical University, ul. Malaya Pirogovskaya 1, Moscow, 119882 Russia
b
Universidad Autonoma Metropolitana, Azcapotzalco, Mexico
c
Karpov Research Institute of Physical Chemistry, ul. Vorontsovo pole 10, Moscow, 103064 Russia
d
Moscow State University, Vorob’evy gory, Moscow, 119899 Russia
Received October 16, 2006
Abstract—Acid nickel oxovanadate, [Ni(H é) ] [H V O ] · 6H O (I) was synthesized and studied by X-ray
2
6 2
2
10 28
2
diffraction analysis, thermogravimetry, powder X-ray diffraction, and IR spectroscopy. The crystals are tri-
clinic: space group ê1 , a = 8.869(2) Å, b = 10.869(2) Å, c = 11.116(2) Å, α = 65.14(3)°, β = 74.11(3)°, γ =
3
3
7
0.47(3)°, V = 907.41 Å , ρ(calcd.) = 2.56 g/cm , Z = 1.
DOI: 10.1134/S1070328407080064
Heteropoly compounds (HPC) represent a class of
The chemical composition of synthesized com-
complex coordination compounds with a unique struc- pound I was established by mass-spectrometry; the
ture [1]. If a central atom of the complex anion and the water of crystallization was determined by TG method.
atoms of transition elements in the composition of a
general ligand are identical, then isopoly compound
IPC) is realized. Different theories of IPC formation
For Ni(H O) ] [H V O ] · 6H O
2
6 2
2
10 28
2
(
anal. calcd.,%: Ni, 8.38; V, 36.44; O, 32.02; H O, 23.16.
2
are considered in the literature [2–8]. The synthesis of
novel compounds with the desired physicochemical
properties and the establishment of regularities govern-
ing the changes in these properties with the changing
compositions and structures are of great importance for
the development of the HPC and IPC chemistry.
An interest in heteropolyvanadates is due to their
use as catalysts in the selective oxidation of organic
compounds, for example, methanol to formaldehyde, V = 907.4 Å , ρ(calcd.) = 2.56 g/cm , Z = 1, space group
benzene to maleic anhydride, and as stabilizers of poly-
mers and oils [9].
The data on vanadates and their use as catalysts in 100 min had unchanged intensities to within ±0.6%. Of
the methane oxidation reaction are reported in [10, 11]. the total 4228 reflections, 3965 were independent
Found, %:
Ni, 8.40; V, 35.96; O, 32.18; H O 23.46.
2
X-ray diffraction analysis was performed on an
Enraf-Nonius CAD4 automated diffractometer (MoKα
radiation, λ = 0.71073 Å) at room temperature. The
crystals are triclinic: a = 8.869(2), b = 10.869(2), c =
1
1.116(2) Å, α = 65.14(3)°, β = 74.11(3)°, γ = 70.47(3)°,
3
3
ê1 .Yellow single crystal 0.24 × 0.18 × 0.15 mm in size
was used. Three control reflections measured every
reflections with I > 2σ(I), the range of angles θ = 2/04°–
The aim of this work was to synthesize and study the
physicochemical properties of acid nickel oxovanadate,
2
6.99° (R = 0.0157).
int
[
Ni(H é) ] [H V O ] · 6H O (I).
2 6 2 2 10 28 2
The structure was solved by the direct method and
refined by the full-matrix least-squares method in
anisotropic approximation for non-hydrogen atoms. An
EXPERIMENTAL
Synthesis of I was performed using the original
procedure. To a hot solution of ammonium metavana-
date acidified with nitric acid to pH 3, a hot solution of
nickel sulfate and ammonium persulfate were added.
The solution obtained was filtered and cooled in desic-
cator over an alkali. In a week, dark yellow crystals of
–1
absorption correction was applied (µ = 3.599 mm ) by
–1
ψ-scanning, ), í = 0.6143, Tmax = 0.4788. The final
min
values R = 0.0232, wR = 0.0649, GOOF = 1.106,
1
2
extinction coefficient 0.0013(5). The calculations were
carried out by the SHELX-97 program package [12].
The atomic coordinates and thermal parameters are
I precipitated; these were filtered off, washed with dis- given in Table 1, the bond lengths and bond angles are
tilled water and ethanol.
listed in Table 2.
5
82

ACID NICKEL OXOVANADATE
583
4
Table 1. Atomic coordinates (×10 ) and equivalent thermal
Powder X-ray diffraction data were obtained on a
3
parameters (×10 ) of [Ni(H O) ] [H V O ] · 6H O
XRD-6000 diffractometer (CuK radiation, Ni filter)
2
6 2
2
10 28
2
α
with silicon used as an external standard. The samples
were preliminarily ground in a jasper mortar. The X-ray
patterns obtained were interpreted in two steps. First,
the position of the peak maximum was determined with
the WinXpow program package. At the second step, the
X-ray patterns were indexed using the Powder-2 pro-
gram package. The phase identification was performed
on the basis of the powder X-ray diffraction database
JCPDS, 2001.
2
Atom
x
y
z
U , Å
eq
Ni
7797(1)
6742(1)
6178(1)
6465(1)
6340(1)
3126(1)
4868(2)
7406(2)
5198(2)
4918(2)
7655(2)
7748(2)
7919(2)
7222(2)
4614(2)
4404(2)
7429(2)
7106(2)
1787(2)
7438(3)
6538(3)
6340(2)
6010(3)
9116(2)
9417(3)
9099(3)
3201(3)
7324(1)
5055(1)
2236(1)
4502(1)
2784(1)
2641(1)
4015(2)
3664(2)
6432(2)
5591(2)
4097(2)
5707(2)
6112(2)
1694(2)
1990(2)
1610(2)
3332(2)
1075(2)
1790(2)
2019(2)
8134(2)
8919(2)
6298(2)
6542(2)
8498(3)
5663(3)
–824(2)
1680(3)
–2161(1)
5199(1)
5514(1)
2720(1)
8004(1)
600(1)
18(1)
14(1)
16(1)
15(1)
19(1)
19(1)
15(1)
15(1)
14(1)
18(1)
19(1)
19(1)
19(1)
19(1)
21(1)
19(1)
24(1)
23(1)
30(1)
31(1)
28(1)
26(1)
29(1)
32(1)
40(1)
43(1)
43(1)
41(1)
47(1)
V(1)
V(2)
V(3)
Thermogravimetric analysis (TGA) of I was car-
ried out on a Paulik–Paulik–Erdey setup in the temper-
ature range of 20–1000°ë (heating rate 10 K/min, a
V(4)
V(5)
4
00 g sample) using calcined alumina as the reference.
IR spectra were recorded on a Perkin Elmer spec-
O(1)
6216(2)
4418(2)
5903(2)
1630(2)
6584(2)
1994(2)
4105(2)
6930(2)
8732(2)
6568(2)
2079(2)
4850(2)
8456(2)
9163(2)
–3755(2)
–1467(2)
–1062(2)
–627(2)
–3325(2)
–2739(3)
7661(3)
5989(2)
–1
trophotometer at 400−4000 cm (KBr pellets).
O(2)
RESULTS AND DISCUSSION
O(3)
The structure of synthesized compound I (Fig. 1)
consists of isopolyanions (IPA), crystallization water
O(4)
2
+
molecule, and hydrated complex cations [Ni(H é) ] .
2
6
O(5)
The Ni atom is coordinated at the vertices of an
octahedron by six O atoms of water molecules. The
Ni−é(w) bond length lies in the interval 2.048(2)–
O(6)
2
.089 Å.
The [ç V O ] IPA consists of ten distorted Vé
6
O(7)
4–
2
10 28
O(8)
octahedra sharing common edges. The O atoms in octa-
hedral surrounding of the vanadium cation have differ-
ent nature of the bonds. The O(1) atom binds six V
atoms of oxometallate sphere. The atoms O(4)–O(10)
form double (V–O–V), while the atoms O(2) and O(3)
form triple bridging bonds. The O(11)−O(14) atoms
form multiple terminal bonds V=é.
O(9)
O(10)
O(11)
O(12)
O(13)
O(14)
O(1w)
O(2w)
O(3w)
O(4w)
O(5w)
O(6w)
O(7w)
6
–
The [V O ] IPA can be schematically presented
10
28
8–
as duplication of the [V O ] polyanions (Fig. 2a, 2b).
6
19
The contacts between IPA, outer-sphere cations and
water molecules are realized through electrostatic inter-
actions and hydrogen bonds. The structure similar to I
was described in [13, 14].
The TGA of I revealed three endotherms (Fig. 3).
The first endotherms at 120 and 140°C correspond to
the removal of the six crystallization and twelve coor-
dinated water molecules, respectively, which results in
crystal structure destruction. The endotherm at 550°ë
corresponds to the IPC decomposition and formation of
the thermolysis products, i.e., oxides of vanadium(V)
and nickel. The thermal decomposition of compound I
can be represented as follows:
1
20°C
[
Ni(H O) ] [H V O ] ⋅ 6H O
[Ni(H O) ]
2
6
2
6H O
2
6
2
2
10 28
2
–
2
1
40°C
550°C
×
[H V O ]
Ni H V O
2NiO ⋅ 5V O .
2 5
–H O
2
2
10 28
2
2
10 28
–
12H O
O(8w) 10715(3)
O(9w) 124(3)
2
In order to confirm the thermal decomposition
scheme, we performed powder X-ray diffraction analy-
612(3) 11145(2)
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 33 No. 8 2007

5
84
KAZIEV et al.
Table 2. Interatomic distances and bond angles in [Ni(H O) ] [H V O ] · 6H O*
2
6 2
2
10 28
2
Bond
d, Å
Bond
d, Å
Bond
d, Å
Bond
d, Å
Ni–O(6w)
Ni–O(5w)
Ni–O(4w)
Ni–O(3w)
Ni–O(1w)
Ni–O(2w)
V(1)–O(7)
V(1)–O(5)
V(1)–O(2)
2.048(2)
2.048(2)
2.052(2)
2.057(2)
2.067(2)
2.089(2)
V(1)–O(1)
V(1)–V(5A)
V(1)–V(4)
V(2)–O(12)
V(2)–O(8)
V(2)–O(10)
2.1167(18) V(2)–V(4)
3.0704(14) V(3)–O(11)
3.0767(14) V(3)–O(6)
1.6055(18) V(3)–O(4)
1.8258(18) V(3)–O(2)
1.8306(19) V(3)–O(3A)
1.9753(18) V(3)–O(1A)
2.0058(19) V(3)–V(5A)
2.2331(17) V(4)–O(14)
3.1154(8) V(4)–O(4A)
1.6016(18) V(4)–O(5)
1.8100(18) V(4)–O(1)
1.8357(19) V(4)–V(5)
1.9989(18) V(5)–O(13)
2.0031(18) V(5)–O(9)
2.2301(17) V(5)–O(10)
1.8918(18)
2.027(2)
2.3370(19)
3.0668(9)
1.598(2)
1.8328(19)
1.8398(18)
1.8977(17)
1.6810(18) V(2)–O(2)
1.6977(19) V(2)–O(3A)
1.9046(17) V(2)–O(1)
3.1147(8)
1.595(2)
V(5)–O(6A)
V(5)–O(7A)
V(5)–O(1)
2.063(2)
V(1)–O(3)
V(1)–O(1A)
Angle
1.9406(17) V(2)–V(3)
2.1122(18) V(2)–V(5)
3.0572(14) V(4)–O(9)
3.0865(13) V(4)–O(8)
1.834(2)
1.8737(18)
ω, deg
2.3023(19)
ω, deg
Angle
ω, deg
Angle
Angle
ω, deg
O(5W)NiO(6w)
O(5W)NiO(4w)
O(6W)NiO(4w)
93.04(10) O(12)V(2)O(8) 103.66(9) O(14)V(4)O(8) 102.71(10) V(1A)O(1)V(1) 101.98(7)
88.44(9) O(12)V(2)O(10) 102.74(9) O(9)V(4)O(8)
89.63(10) O(8)V(2)O(10)
90.81(8) V(1A)O(1)V(3A) 92.72(7)
93.91(6)
94.00(8) O(14)V(4)O(4A) 101.87(10) V(1)O(1)V(3A)
O(5W)NiO(3w) 174.95(9) O(12)V(2)O(2)
99.70(9) O(9)V(4)O(4A)
90.69(8) V(1A)O(1)V(2)
93.95(7)
92.21(6)
O(6W)NiO(3w)
O(4W)NiO(3w)
O(5W)NiO(1w)
O(6W)NiO(1w)
90.36(9) O(8)V(2)O(2)
91.12(8) O(8)V(4)O(4A) 154.36(8) V(1)O(1)V(2)
95.31(9) O(10)V(2)O(2) 155.06(7) O(14)V(4)O(5) 101.24(10) V(3A)O(1)V(2) 169.83(8)
89.62(9) O(12)V(2)O(3A) 98.66(9) O(9)V(4)O(5)
89.83(10) O(8)V(2)O(3A) 156.14(7) O(8)V(4)O(5)
155.74(8) V(1A)O(1)V(5)
84.57(8) V(1)O(1)V(5)
88.03(7)
169.91(8)
O(4W)NiO(1w) 177.96(8) O(10)V(2)O(3A) 89.15(8) O(4A)V(4)O(5) 83.61(8)
V(3A)O(1)V(5) 86.80(6)
O(3W)NiO(1w)
O(5W)NiO(2w)
86.66(8) O(2)V(2)O(3A)
76.78(7) O(14)V(4)O(1) 175.62(9) V(2)O(1)V(5)
85.76(6)
91.59(9) O(12)V(2)O(1) 173.94(8) O(9)V(4)O(1)
81.35(7) V(1A)O(1)V(4) 170.77(8)
O(6W)NiO(2w) 175.36(9) O(8)V(2)O(1)
81.21(7) O(8)V(4)O(1)
80.29(7) O(4A)V(4)O(1)
76.40(7) O(5)V(4)O(1)
76.02(7) O(6)V(3)O(4)
77.49(7) V(1)O(1)V(4)
77.44(7) V(3A)O(1)V(4)
74.39(7) V(2)O(1)V(4)
95.56(8) V(5)O(1)V(4)
87.24(7)
86.27(6)
85.92(6)
82.76(6)
107.82(8)
107.26(8)
100.57(8)
O(4W)NiO(2w)
O(3W)NiO(2w)
O(1W)NiO(2w)
O(7)V(1)O(5)
O(7)V(1)O(2)
O(5)V(1)O(2)
O(7)V(1)O(3)
O(5)V(1)O(3)
O(2)V(1)O(3)
O(7)V(1)O(1A)
90.20(9) O(10)V(2)O(1)
85.03(8) O(2)V(2)O(1)
90.50(8) O(3A)V(2)O(1)
106.93(9) O(11)V(3)O(6) 102.12(9) O(13)V(5)O(9) 103.44(10) V(1)O(2)V(2)
98.40(8) O(11)V(3)O(4) 102.20(9) O(13)V(5)O(10) 102.46(9) V(1)O(2)V(3)
97.82(8) O(11)V(3)O(2)
96.43(8) O(6)V(3)O(2)
96.29(8) O(4)V(3)O(2)
99.76(9) O(9)V(5)O(10)
93.25(8) V(2)O(2)V(3)
89.96(8) O(13)V(5)O(6A) 101.38(9) V(1)O(3)V(3A) 107.35(8)
155.65(7) O(9)V(5)O(6A) 90.71(8) V(1)O(3)V(2A) 107.25(8)
155.57(7) O(11)V(3)O(3A) 100.54(9) O(10)V(5)O(6A) 154.18(8) V(3A)O(3)V(2A) 99.39(8)
87.75(8) O(6)V(3)O(3A) 155.19(7) O(13)V(5)O(7A) 99.72(10) V(3)O(4)V(4A) 113.85(9)
O(5)V(1)O(1A) 165.26(8) O(4)V(3)O(3A)
89.40(8) O(9)V(5)O(7A) 156.72(8) V(1)O(5)V(4)
111.08(9)
O(2)V(1)O(1A)
O(3)V(1)O(1A)
O(7)V(1)O(1)
O(5)V(1)O(1)
O(2)V(1)O(1)
O(3)V(1)O(1)
O(1A)V(1)O(1)
81.00(7) O(2)V(3)O(3A)
76.31(7) O(10)V(5)O(7)
83.89(8) V(3)O(6)V(5A) 114.27(9)
82.47(8) V(1)O(7)V(5A) 109.78(9)
80.30(7) O(11)V(3)O(1A) 175.12(8) O(6A)V(5)O(7)
165.71(8) O(6)V(3)O(1A)
80.67(7) O(13)V(5)O(1) 174.07(9) V(2)O(8)V(4)
114.72(9)
113.51(9)
114.47(9)
87.28(8) O(4)V(3)O(1A)
80.77(7) O(2)V(3)O(1A)
81.40(7) O(9)V(5)O(1)
76.12(7) O(10)V(5)O(1)
82.35(7) V(5)O(9)V(4)
78.24(7) V(5)O(10)V(5)
77.03(7)
80.09(7) O(3A)V(3)O(1A) 76.05(6) O(6A)V(5)O(1)
78.02(7) O(14)V(4)O(9) 103.01(10) O(7A)V(5)O(1)
74.44(7)
*
Symmetry transformations: (A) –x + 1, –y + 1, –z + 1.
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 33 No. 8 2007

ACID NICKEL OXOVANADATE
585
1
(w)
2
(w)
O(12)
O(11)
V(3)
(5w)
3
(w)
O(4)
O(3A)
(3w)
O(2)
O(10)
O(6)
O(14)
O(2)
O(5A)
O(8)
V(5)
O(7A)
Ni
(
V(4A)
V(1A)
(2w)
(4w)
O(9A)
O(1A)
Ni(A)
O(13)
O(9)
(
1w)
6w)
O(1)
V(5A)
V(1)
V(4)
O(13A)
O(7)
O(6A)
O(5A)
O(2A)
O(8A)
O(14)
4
(w)
V(2A)
O(10A)
V(3A)
O(4A)
O(3)
5
(w)
O(12A)
O(11A)
6
(w)
Fig. 1. Crystal structure of isopolyanion I.
(
a)
(b)
V2
V'
1
V2
V'
1
V1
+
=
+
V1
8
–
8–
6–
10–
[
V O ]
[V'O ]
[V O ]
[V O ]
2 10
6
19
6
19
10 28
Fig. 2. Scheme of isopolyanion I formation.
sis of both I (Table 3) and of the thermolysis products
using PCPDFWIN database. The X-ray diffraction pat-
terns obtained at room temperature and after the first
endotherm are identical, which indicates the retention
of the IPC crystal structure. The X-ray diffraction pat-
tern obtained after the third endotherm suggests the
Ni H V O decomposition and formation of the ther-
molysis products indicated in the scheme. The powder
X-ray diffraction data of the thermal decomposition
products are given in Table 4.
T, °C
∆m, %
TG
900
700
500
300
1
2
0
0
5
50
DTA
2
2
10 28
IR spectrum of compound I contains three groups of
30
60
T
–1
100
0
absorption bands at 400–1000 cm corresponding to
vibrations of different vanadium–oxygen bonds of the
complex IPA [15, 16]. The intense band in a range of
140
30
Time, min
–1
9
00−1100 cm belongs to the terminal cis-V=O bonds.
The stretching vibrations of the bridging bonds
v(V−O–V) and v (V−O–V) appear as a doublet at 685
s
as
–1
Fig. 3. Thermoderivatogram of compound I.
and 420 cm , respectively. The bands at 589 and
RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 33 No. 8 2007

5
86
KAZIEV et al.
Table
3. Powder
X-ray
diffraction
data
for Table 4. Powder X-ray diffraction data for the products of
[
Ni(H O) ] [H V O ] · 6H O
[Ni(H O) ] [H V O ] · 6H O thermal decomposition*
2
6 2
2
10 28
2
2
6 2
2
10 28
2
Peak no.
2θ, deg
d, Å
I, %
Peak no. 2θ, deg d, Å
I, %
h
k
l
1
2
3
4
5
6
7
8
9
17.51
22.31
24.67
26.11
28.65
30.12
32.64
33.56
35.13
36.12
38.45
40.12
41.46
43.14
44.23
45.63
46.86
46.43
48.64
50.31
53.12
55.23
56.12
5.47
5.26
5.10
4.97
3.64
3.52
3.39
3.34
3.12
3.05
2.79
2.70
2.65
2.45
2.39
2.27
2.21
2.18
2.11
2.06
1.98
1.87
1.81
9.12
23.12
14.34
13.21
26.54
23.45
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
17.52
21.03
24.97
27.49
29.50
30.86
32.88
35.84
37.19
38.55
39.82
42.86
46.59
47.62
49.84
50.22
51.15
57.03
57.68
58.11
5.87
4.90
4.13
3.76
3.51
3.36
41.54
70.61
39.41
44.71
16.40
6.73
0
2
2
2
2
2
1
4
3
1
2
4
4
2
2
2
2
2
2
1
2
0
2
2
2
0
2
0
1
3
4
0
2
4
5
4
5
4
5
0
0
–1
0
–1
1
100
–2
–2
0
21.43
41.45
15.45
11.33
16.08
15.87
12.59
18.76
10.99
19.87
20.14
8.56
3.15 100
76.50
2.90
2.80
2.70
2.62
2.44
2.26
2.21
2.12
2.10
2.07
1.87
1.85
1.84
1
0
10.00
13.86
11.59
23.67
2.48
–2
–2
0
11
1
1
1
1
1
1
1
1
2
2
2
3
4
5
6
7
8
9
0
1
1
1
1
1
1
1
1
1
1
1
2
–2
–2
–2
–1
2
4.43
14.04
10.80
5.76
16.44
12.34
11.23
10.21
1
5.88
–3
2
22
2
3
9.84
*
Peaks no. 2, 5, 9, 14, 16, and 20 belong to NiO, the remaining
peaks refer to V O .
5.80
4
2
5
–
1
8
06 cm are due to different types of the vanadium–
ACKNOWLEDGMENTS
oxygen bridging bonds, i.e., V(3)–O, V(4)–O. The band
at 850 cm is produced by the Ni–O bond vibrations.
The absorption bands observed in IR spectrum in the
regions of 1632 and 3439 cm correspond to the vibra-
tions of water molecules.
This work was supported by the Russian Foundation
for Basic Research (project no. 05-03-32432).
–1
–1
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1
2
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of
IR
spectrum
of
[
Ni(H é) ] [ç V O ] · 6H O to the spectra of the pre-
2
6 2
2
10 28
2
viously studied IPC confirms our suggestion on their
3. Maksimov, G.V., Usp. Khim., 1995, vol. 64, no. 5,
p. 480.
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4
5
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RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 33 No. 8 2007

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RUSSIAN JOURNAL OF COORDINATION CHEMISTRY Vol. 33 No. 8 2007