Trichlorido(4-methyl­benz­yl)bis­(1H-pyrazole-κN2)tin(IV)

Keng, T.C.; Lo, K.M.; Ng, S.W.

doi:10.1107/S1600536811015698

metal-organic compounds

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ISSN: 2056-9890

Volume 67| Part 6| June 2011| Page m659

doi:10.1107/S1600536811015698

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Trichlorido(4-methylbenzyl)bis(1H-pyrazole-κN²)tin(IV)

Thy Chun Keng,^a Kong Mun Lo ^a and Seik Weng Ng ^a ^*

^aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 20 April 2011; accepted 26 April 2011; online 7 May 2011)

The six-coordinate Sn^IV atom in the title compound, [Sn(C₈H₉)Cl₃(C₃H₄N₂)₂], shows an octahedral coordination. The N atoms of the N-heterocycle are cis to each other. The Sn—N bond that is trans to the Sn—C bond is shorter than the Sn—N bond trans to the Sn—Cl bond. Weak N—H⋯Cl hydrogen bonds link adjacent molecules, generating a double chain running along the c axis.

Related literature

For the direct synthesis of the organotin chloride reactant, see: Sisido et al. (1961 ). For the trichloridophenyltin–di(pyrazole) adduct, see: Casas et al. (1996 ).

Experimental

Crystal data

[Sn(C₈H₉)Cl₃(C₃H₄N₂)₂]
M_r = 466.36
Monoclinic, C 2/c
a = 34.7322 (4) Å
b = 7.3709 (1) Å
c = 14.5760 (2) Å
β = 109.0535 (5)°
V = 3527.13 (8) Å³
Z = 8
Mo Kα radiation
μ = 1.90 mm⁻¹
T = 100 K
0.30 × 0.25 × 0.20 mm

Data collection

Bruker SMART APEX diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.599, T_max = 0.702
16131 measured reflections
4053 independent reflections
3734 reflections with I > 2σ(I)
R_int = 0.022

Refinement

R[F² > 2σ(F²)] = 0.017
wR(F²) = 0.044
S = 1.00
4053 reflections
208 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.43 e Å⁻³
Δρ_min = −0.26 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2⋯Cl1ⁱ	0.87 (1)	2.56 (2)	3.265 (2)	139 (2)
N4—H4⋯Cl1ⁱⁱ	0.88 (1)	2.65 (2)	3.270 (2)	129 (2)
Symmetry codes: (i) $[-x+1, y, -z+{\script{3\over 2}}]$ ; (ii) $[x, -y+1, z-{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker, 2009 ); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811015698/bt5524sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811015698/bt5524Isup2.hkl

checkCIF report

Comment top

Dibenzyltin dichloride and benzyltin trichloride can be synthesized by the direct action of benzyl chloride on stannous chloride; other ring-substituted analogs are similarly synthesized (Sisido et al., 1961). The title compound results from the reaction of di(4-methylbenzyl)tin dichloride with pyrazole to afford the pyrazole adduct of a monoorganotin trichloride. There are few examples of monororganotin chlorides forming adducts with N-heterocycles. Phenyltin trichloride forms a 1:2 adduct with pyrazole (Casas et al., 1996). The 4-methylbenzyl analog affords a similar 1:2 adduct. The six-coordinate Sn^IV atom in SnCl₃(C₈H₉)(C₃H₄N₂)₂ (Scheme I) shows octahedral coordination. The N atoms of the N-heterocycle are cis to each other and the three Cl atoms are coplanar (Fig. 1). The geometry can be described as being a mer-octahedron. The Sn–N bond that is trans to the Sn–C bond is shorter than the Sn–N bond trans to the Sn–Cl bond.

Related literature top

For the direct synthesis of the organotin chloride reactant, see: Sisido et al. (1961). For the trichloridophenyltin–di(pyrazole) adduct, see: Casas et al. (1996).

Experimental top

Di(4-methylbenzyl)tin dichloride was synthesized by using a literature procedure (Sisido et al., 1961). The compound (0.4 g, 1 mmol) and pyrazole (0.136 g, 2 mmol) of pyrazole were dissolved in ethanol (100 ml) and the solution was heated for an hour. The solution was filtered and then set aside for the growth of colorless crystals.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top

Fig. 1. Anisotropic displacement ellipsoid plot (Barbour, 2001) of SnCl₃(C₈H₉)(C₃H₄N₂)₂ at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius.

Trichlorido(4-methylbenzyl)bis(1H-pyrazole-κN²)tin(IV) top

Crystal data top

[Sn(C₈H₉)Cl₃(C₃H₄N₂)₂]	F(000) = 1840
M_r = 466.36	D_x = 1.756 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 9748 reflections
a = 34.7322 (4) Å	θ = 2.5–28.3°
b = 7.3709 (1) Å	µ = 1.90 mm⁻¹
c = 14.5760 (2) Å	T = 100 K
β = 109.0535 (5)°	Block, colorless
V = 3527.13 (8) Å³	0.30 × 0.25 × 0.20 mm
Z = 8

Data collection top

Bruker SMART APEX diffractometer	4053 independent reflections
Radiation source: fine-focus sealed tube	3734 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.022
ω scans	θ_max = 27.5°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −44→44
T_min = 0.599, T_max = 0.702	k = −9→9
16131 measured reflections	l = −18→18

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.017	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.044	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	w = 1/[σ²(F_o²) + (0.022P)² + 3.9233P] where P = (F_o² + 2F_c²)/3
4053 reflections	(Δ/σ)_max = 0.001
208 parameters	Δρ_max = 0.43 e Å⁻³
2 restraints	Δρ_min = −0.26 e Å⁻³

Crystal data top

[Sn(C₈H₉)Cl₃(C₃H₄N₂)₂]	V = 3527.13 (8) Å³
M_r = 466.36	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 34.7322 (4) Å	µ = 1.90 mm⁻¹
b = 7.3709 (1) Å	T = 100 K
c = 14.5760 (2) Å	0.30 × 0.25 × 0.20 mm
β = 109.0535 (5)°

Data collection top

Bruker SMART APEX diffractometer	4053 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3734 reflections with I > 2σ(I)
T_min = 0.599, T_max = 0.702	R_int = 0.022
16131 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.017	2 restraints
wR(F²) = 0.044	H atoms treated by a mixture of independent and constrained refinement
S = 1.00	Δρ_max = 0.43 e Å⁻³
4053 reflections	Δρ_min = −0.26 e Å⁻³
208 parameters

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Sn1	0.595182 (3)	0.582348 (14)	0.721693 (7)	0.01211 (4)
Cl1	0.555981 (12)	0.42823 (5)	0.81341 (3)	0.01619 (8)
Cl2	0.626900 (12)	0.79953 (6)	0.85059 (3)	0.01902 (9)
Cl3	0.556206 (12)	0.41810 (5)	0.57311 (3)	0.01787 (9)
N1	0.54480 (4)	0.77932 (19)	0.67420 (10)	0.0150 (3)
N2	0.50505 (4)	0.7311 (2)	0.64558 (11)	0.0183 (3)
H2	0.4985 (7)	0.6177 (16)	0.6474 (18)	0.038 (7)*
N3	0.62026 (4)	0.74995 (19)	0.62547 (10)	0.0153 (3)
N4	0.60725 (4)	0.7316 (2)	0.52785 (10)	0.0166 (3)
H4	0.5873 (5)	0.657 (3)	0.4997 (15)	0.031 (6)*
C1	0.64493 (5)	0.3890 (2)	0.76417 (13)	0.0179 (3)
H1A	0.6574	0.3912	0.8357	0.021*
H1B	0.6339	0.2657	0.7453	0.021*
C2	0.67715 (5)	0.4263 (2)	0.71934 (13)	0.0161 (3)
C3	0.67158 (5)	0.3774 (2)	0.62338 (13)	0.0172 (3)
H3	0.6472	0.3172	0.5866	0.021*
C4	0.70114 (5)	0.4155 (2)	0.58085 (13)	0.0192 (4)
H4A	0.6967	0.3807	0.5154	0.023*
C5	0.73723 (5)	0.5037 (2)	0.63237 (13)	0.0179 (3)
C6	0.74257 (5)	0.5557 (2)	0.72790 (13)	0.0181 (3)
H6	0.7667	0.6179	0.7642	0.022*
C7	0.71300 (5)	0.5175 (2)	0.77065 (12)	0.0174 (3)
H7	0.7173	0.5539	0.8357	0.021*
C8	0.76965 (6)	0.5415 (3)	0.58673 (14)	0.0252 (4)
H8A	0.7843	0.6527	0.6145	0.038*
H8B	0.7569	0.5566	0.5165	0.038*
H8C	0.7888	0.4397	0.5995	0.038*
C9	0.54488 (6)	0.9595 (2)	0.66532 (15)	0.0234 (4)
H9	0.5687	1.0325	0.6800	0.028*
C10	0.50533 (6)	1.0249 (3)	0.63159 (15)	0.0255 (4)
H10	0.4970	1.1478	0.6191	0.031*
C11	0.48082 (5)	0.8757 (2)	0.62004 (12)	0.0187 (3)
H11	0.4519	0.8751	0.5979	0.022*
C12	0.65211 (5)	0.8626 (2)	0.64665 (13)	0.0177 (3)
H12	0.6676	0.9003	0.7103	0.021*
C13	0.65924 (6)	0.9165 (2)	0.56243 (14)	0.0226 (4)
H13	0.6799	0.9963	0.5572	0.027*
C14	0.63001 (6)	0.8300 (2)	0.48815 (13)	0.0215 (4)
H14	0.6266	0.8385	0.4209	0.026*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Sn1	0.01177 (6)	0.01333 (6)	0.01165 (6)	−0.00092 (4)	0.00438 (4)	−0.00068 (4)
Cl1	0.01552 (18)	0.01766 (19)	0.01712 (19)	0.00114 (14)	0.00767 (15)	0.00354 (15)
Cl2	0.01874 (19)	0.0214 (2)	0.01536 (18)	−0.00281 (15)	0.00349 (15)	−0.00550 (15)
Cl3	0.0199 (2)	0.01818 (19)	0.01524 (19)	−0.00530 (15)	0.00538 (15)	−0.00409 (15)
N1	0.0132 (6)	0.0161 (7)	0.0157 (7)	−0.0021 (5)	0.0047 (5)	−0.0007 (5)
N2	0.0138 (7)	0.0173 (7)	0.0225 (7)	−0.0023 (6)	0.0041 (6)	−0.0002 (6)
N3	0.0163 (6)	0.0172 (7)	0.0124 (6)	−0.0017 (5)	0.0048 (5)	−0.0013 (5)
N4	0.0196 (7)	0.0167 (7)	0.0134 (6)	−0.0020 (6)	0.0052 (6)	−0.0002 (6)
C1	0.0167 (8)	0.0177 (8)	0.0199 (8)	0.0016 (6)	0.0070 (7)	0.0023 (7)
C2	0.0152 (8)	0.0142 (8)	0.0194 (8)	0.0023 (6)	0.0063 (6)	0.0007 (6)
C3	0.0136 (7)	0.0172 (8)	0.0204 (8)	0.0005 (6)	0.0047 (6)	−0.0030 (7)
C4	0.0191 (8)	0.0215 (9)	0.0178 (8)	0.0032 (7)	0.0071 (7)	−0.0022 (7)
C5	0.0156 (8)	0.0167 (8)	0.0225 (9)	0.0033 (6)	0.0077 (7)	0.0029 (7)
C6	0.0137 (8)	0.0160 (8)	0.0231 (9)	0.0006 (6)	0.0039 (7)	0.0002 (7)
C7	0.0174 (8)	0.0181 (8)	0.0157 (8)	0.0022 (6)	0.0042 (6)	−0.0012 (7)
C8	0.0208 (9)	0.0311 (10)	0.0270 (10)	0.0004 (8)	0.0124 (8)	0.0025 (8)
C9	0.0198 (9)	0.0155 (8)	0.0351 (10)	−0.0020 (7)	0.0090 (8)	0.0019 (8)
C10	0.0234 (9)	0.0171 (8)	0.0358 (11)	0.0039 (7)	0.0095 (8)	0.0055 (8)
C11	0.0160 (8)	0.0226 (9)	0.0174 (8)	0.0026 (7)	0.0055 (7)	−0.0001 (7)
C12	0.0173 (8)	0.0168 (8)	0.0193 (8)	−0.0028 (6)	0.0066 (7)	−0.0010 (7)
C13	0.0270 (9)	0.0193 (9)	0.0266 (10)	−0.0049 (7)	0.0156 (8)	−0.0012 (7)
C14	0.0319 (10)	0.0176 (9)	0.0193 (8)	−0.0008 (7)	0.0141 (8)	0.0019 (7)

Geometric parameters (Å, º) top

Sn1—C1	2.1680 (17)	C4—C5	1.394 (2)
Sn1—N1	2.2042 (14)	C4—H4A	0.9500
Sn1—N3	2.2471 (14)	C5—C6	1.397 (2)
Sn1—Cl2	2.4402 (4)	C5—C8	1.509 (2)
Sn1—Cl3	2.4646 (4)	C6—C7	1.393 (2)
Sn1—Cl1	2.4739 (4)	C6—H6	0.9500
N1—C9	1.334 (2)	C7—H7	0.9500
N1—N2	1.3528 (19)	C8—H8A	0.9800
N2—C11	1.333 (2)	C8—H8B	0.9800
N2—H2	0.869 (10)	C8—H8C	0.9800
N3—C12	1.336 (2)	C9—C10	1.386 (3)
N3—N4	1.3518 (19)	C9—H9	0.9500
N4—C14	1.336 (2)	C10—C11	1.368 (3)
N4—H4	0.876 (9)	C10—H10	0.9500
C1—C2	1.494 (2)	C11—H11	0.9500
C1—H1A	0.9900	C12—C13	1.388 (2)
C1—H1B	0.9900	C12—H12	0.9500
C2—C3	1.395 (2)	C13—C14	1.376 (3)
C2—C7	1.398 (2)	C13—H13	0.9500
C3—C4	1.390 (2)	C14—H14	0.9500
C3—H3	0.9500

C1—Sn1—N1	178.30 (6)	C2—C3—H3	119.5
C1—Sn1—N3	96.00 (6)	C3—C4—C5	121.27 (16)
N1—Sn1—N3	82.62 (5)	C3—C4—H4A	119.4
C1—Sn1—Cl2	95.39 (5)	C5—C4—H4A	119.4
N1—Sn1—Cl2	85.54 (4)	C6—C5—C4	117.92 (16)
N3—Sn1—Cl2	87.15 (4)	C6—C5—C8	120.91 (16)
C1—Sn1—Cl3	94.93 (5)	C4—C5—C8	121.17 (16)
N1—Sn1—Cl3	84.01 (4)	C5—C6—C7	120.88 (16)
N3—Sn1—Cl3	86.29 (4)	C5—C6—H6	119.6
Cl2—Sn1—Cl3	168.293 (15)	C7—C6—H6	119.6
C1—Sn1—Cl1	94.11 (5)	C2—C7—C6	121.07 (16)
N1—Sn1—Cl1	87.23 (4)	C2—C7—H7	119.5
N3—Sn1—Cl1	169.61 (4)	C6—C7—H7	119.5
Cl2—Sn1—Cl1	94.297 (14)	C5—C8—H8A	109.5
Cl3—Sn1—Cl1	90.458 (14)	C5—C8—H8B	109.5
C9—N1—N2	105.40 (14)	H8A—C8—H8B	109.5
C9—N1—Sn1	131.25 (12)	C5—C8—H8C	109.5
N2—N1—Sn1	123.34 (11)	H8A—C8—H8C	109.5
C11—N2—N1	111.34 (14)	H8B—C8—H8C	109.5
C11—N2—H2	128.9 (16)	N1—C9—C10	110.35 (16)
N1—N2—H2	119.7 (16)	N1—C9—H9	124.8
C12—N3—N4	105.80 (13)	C10—C9—H9	124.8
C12—N3—Sn1	131.13 (11)	C11—C10—C9	105.59 (16)
N4—N3—Sn1	122.52 (10)	C11—C10—H10	127.2
C14—N4—N3	111.11 (14)	C9—C10—H10	127.2
C14—N4—H4	129.0 (15)	N2—C11—C10	107.31 (15)
N3—N4—H4	119.8 (15)	N2—C11—H11	126.3
C2—C1—Sn1	113.26 (11)	C10—C11—H11	126.3
C2—C1—H1A	108.9	N3—C12—C13	110.31 (15)
Sn1—C1—H1A	108.9	N3—C12—H12	124.8
C2—C1—H1B	108.9	C13—C12—H12	124.8
Sn1—C1—H1B	108.9	C14—C13—C12	105.33 (16)
H1A—C1—H1B	107.7	C14—C13—H13	127.3
C3—C2—C7	117.93 (15)	C12—C13—H13	127.3
C3—C2—C1	120.81 (15)	N4—C14—C13	107.45 (16)
C7—C2—C1	121.21 (15)	N4—C14—H14	126.3
C4—C3—C2	120.92 (16)	C13—C14—H14	126.3
C4—C3—H3	119.5

N3—Sn1—N1—C9	−43.97 (16)	Cl3—Sn1—C1—C2	86.69 (12)
Cl2—Sn1—N1—C9	43.73 (16)	Cl1—Sn1—C1—C2	177.50 (12)
Cl3—Sn1—N1—C9	−130.99 (16)	Sn1—C1—C2—C3	−78.65 (18)
Cl1—Sn1—N1—C9	138.26 (16)	Sn1—C1—C2—C7	98.78 (16)
N3—Sn1—N1—N2	135.10 (13)	C7—C2—C3—C4	1.1 (2)
Cl2—Sn1—N1—N2	−137.20 (12)	C1—C2—C3—C4	178.60 (16)
Cl3—Sn1—N1—N2	48.08 (12)	C2—C3—C4—C5	−0.1 (3)
Cl1—Sn1—N1—N2	−42.67 (12)	C3—C4—C5—C6	−1.0 (3)
C9—N1—N2—C11	−0.37 (19)	C3—C4—C5—C8	178.73 (17)
Sn1—N1—N2—C11	−179.64 (11)	C4—C5—C6—C7	1.1 (2)
C1—Sn1—N3—C12	−70.61 (15)	C8—C5—C6—C7	−178.67 (17)
N1—Sn1—N3—C12	110.39 (15)	C3—C2—C7—C6	−1.0 (3)
Cl2—Sn1—N3—C12	24.52 (15)	C1—C2—C7—C6	−178.52 (16)
Cl3—Sn1—N3—C12	−165.19 (15)	C5—C6—C7—C2	−0.1 (3)
Cl1—Sn1—N3—C12	122.84 (19)	N2—N1—C9—C10	0.2 (2)
C1—Sn1—N3—N4	99.62 (13)	Sn1—N1—C9—C10	179.44 (13)
N1—Sn1—N3—N4	−79.38 (12)	N1—C9—C10—C11	0.0 (2)
Cl2—Sn1—N3—N4	−165.25 (12)	N1—N2—C11—C10	0.3 (2)
Cl3—Sn1—N3—N4	5.04 (12)	C9—C10—C11—N2	−0.2 (2)
Cl1—Sn1—N3—N4	−66.9 (3)	N4—N3—C12—C13	0.26 (19)
C12—N3—N4—C14	−0.20 (19)	Sn1—N3—C12—C13	171.71 (12)
Sn1—N3—N4—C14	−172.56 (11)	N3—C12—C13—C14	−0.2 (2)
N3—Sn1—C1—C2	−0.09 (13)	N3—N4—C14—C13	0.1 (2)
Cl2—Sn1—C1—C2	−87.78 (12)	C12—C13—C14—N4	0.1 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···Cl1ⁱ	0.87 (1)	2.56 (2)	3.265 (2)	139 (2)
N4—H4···Cl1ⁱⁱ	0.88 (1)	2.65 (2)	3.270 (2)	129 (2)

Symmetry codes: (i) −x+1, y, −z+3/2; (ii) x, −y+1, z−1/2.

Experimental details

Crystal data
Chemical formula	[Sn(C₈H₉)Cl₃(C₃H₄N₂)₂]
M_r	466.36
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	100
a, b, c (Å)	34.7322 (4), 7.3709 (1), 14.5760 (2)
β (°)	109.0535 (5)
V (Å³)	3527.13 (8)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	1.90
Crystal size (mm)	0.30 × 0.25 × 0.20

Data collection
Diffractometer	Bruker SMART APEX diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.599, 0.702
No. of measured, independent and observed [I > 2σ(I)] reflections	16131, 4053, 3734
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.017, 0.044, 1.00
No. of reflections	4053
No. of parameters	208
No. of restraints	2
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.43, −0.26

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···Cl1ⁱ	0.87 (1)	2.56 (2)	3.265 (2)	139 (2)
N4—H4···Cl1ⁱⁱ	0.88 (1)	2.65 (2)	3.270 (2)	129 (2)

Symmetry codes: (i) −x+1, y, −z+3/2; (ii) x, −y+1, z−1/2.

Acknowledgements

We thank the University of Malaya (grant No. RG020/09AFR) for supporting this study.

References

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