Di­chloro­bis(1,2-phenyl­enedi­amine)­nickel(II)

The title compound, [NiCl₂(C₆H₈N₂)₂], contains centrosymmetric mol­ecules with two phenyl­ene­di­amine ligands coordinated in a bidentate fashion. The Ni-N distances are 2.088 (1) and 2.096 (1) Å, and the Ni-Cl distance of 2.4635 (4) Å. The plane of each phenyl­enedi­amine mol­ecule makes a dihedral angle of 26.53 (7)° with the NiN₄ plane. Extensive hydrogen bonding leads to distinct cleavage in the bc plane.

S1. Comment

The title compound, (I), was prepared for use as a starting material in the synthesis of Haldane Gap systems (Haldane, 1983). The latter can be realised by linear-chain systems of antiferromagnetically coupled S = 1 species.

S2. Experimental

The title compound was prepared by the reaction of 1,2-phenylenediamine dihydrochloride (0.989 g, 5.46 mmol) with NiCl₂·6H₂O (0.386 g, 2.00 mmol) in water (30 ml) under a nitrogen atmosphere for 5 d. The solution was then stored in a sealed tube at room temperature. After 8 d, brown rod-shaped crystals had formed. They were removed by filtration and washed with cold water.

Computing details

Data collection: SMART (Bruker, 1996); cell refinement: SAINT (Bruker, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); software used to prepare material for publication: SHELXL97.

(I)

Crystal data

[NiCl2(C6H8N2)2]	F(000) = 356
Mr = 345.90	Dx = 1.546 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 11.3793 (2) Å	Cell parameters from 4572 reflections
b = 5.9240 (1) Å	θ = 2.0–28.2°
c = 12.1901 (1) Å	µ = 1.66 mm^−1
β = 115.31°	T = 213 K
V = 742.84 (2) Å^3	Block, green
Z = 2	0.35 × 0.20 × 0.15 mm

Data collection

CCD diffractometer	1758 independent reflections
Radiation source: fine-focus sealed tube	1702 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.022
ω scans	θmax = 28.2°, θmin = 2.0°
Absorption correction: empirical (using intensity measurements) (SADABS; Bruker, 1996)	h = −15→10
Tmin = 0.650, Tmax = 0.780	k = −7→7
4572 measured reflections	l = −15→16

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.023	All H-atom parameters refined
wR(F^2) = 0.057	w = 1/[σ^2(Fo^2) + (0.0134P)^2 + 0.3976P] where P = (Fo^2 + 2Fc^2)/3
S = 1.22	(Δ/σ)max = 0.001
1758 reflections	Δρmax = 0.25 e Å^−3
121 parameters	Δρmin = −0.19 e Å^−3
0 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0137 (12)

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Ni	0.0000	0.0000	0.5000	0.02065 (10)
N1	0.15376 (14)	0.1992 (2)	0.50529 (12)	0.0256 (3)
C1	0.24839 (15)	0.2187 (3)	0.63023 (14)	0.0258 (3)
C6	0.33793 (17)	0.3950 (3)	0.67172 (17)	0.0328 (4)
Cl1	−0.06884 (5)	0.29160 (7)	0.60437 (4)	0.03327 (12)
N2	0.14354 (14)	−0.1131 (2)	0.66630 (12)	0.0249 (3)
C4	0.41579 (18)	0.2542 (4)	0.87636 (18)	0.0412 (4)
C2	0.24329 (15)	0.0582 (3)	0.71265 (14)	0.0254 (3)
C3	0.32741 (17)	0.0765 (3)	0.83549 (15)	0.0334 (4)
C5	0.42118 (19)	0.4133 (4)	0.79457 (19)	0.0411 (4)
H2	0.473 (2)	0.270 (4)	0.961 (2)	0.053 (7)*
H6	0.342 (2)	0.504 (3)	0.616 (2)	0.036 (6)*
H2B	0.173 (2)	−0.236 (4)	0.651 (2)	0.040 (6)*
H1B	0.131 (2)	0.335 (4)	0.4713 (19)	0.038 (6)*
H2A	0.119 (2)	−0.153 (4)	0.721 (2)	0.040 (6)*
H3	0.318 (2)	−0.032 (3)	0.8894 (19)	0.035 (5)*
H5	0.480 (2)	0.534 (4)	0.820 (2)	0.046 (6)*
H1A	0.184 (2)	0.125 (4)	0.462 (2)	0.041 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni	0.02621 (15)	0.01932 (15)	0.01932 (14)	0.00204 (10)	0.01250 (11)	0.00226 (10)
N1	0.0322 (7)	0.0232 (7)	0.0252 (6)	0.0017 (6)	0.0160 (6)	0.0039 (5)
C1	0.0253 (7)	0.0268 (8)	0.0283 (8)	0.0042 (6)	0.0145 (6)	0.0018 (6)
C6	0.0299 (8)	0.0328 (9)	0.0390 (9)	0.0003 (7)	0.0179 (7)	0.0019 (8)
Cl1	0.0536 (3)	0.0254 (2)	0.0309 (2)	0.01126 (17)	0.02775 (19)	0.00333 (15)
N2	0.0324 (7)	0.0227 (7)	0.0231 (6)	0.0039 (6)	0.0153 (6)	0.0039 (5)
C4	0.0307 (9)	0.0552 (12)	0.0314 (9)	0.0010 (8)	0.0072 (7)	−0.0037 (8)
C2	0.0256 (7)	0.0277 (8)	0.0262 (7)	0.0052 (6)	0.0142 (6)	0.0022 (6)
C3	0.0300 (8)	0.0428 (10)	0.0269 (8)	0.0051 (7)	0.0116 (7)	0.0038 (7)
C5	0.0307 (9)	0.0445 (11)	0.0456 (11)	−0.0071 (8)	0.0138 (8)	−0.0083 (9)

Geometric parameters (Å, º)

Ni—N1^i	2.0883 (14)	C1—C6	1.394 (2)
Ni—N1	2.0883 (14)	C1—C2	1.402 (2)
Ni—N2^i	2.0964 (13)	C6—C5	1.392 (3)
Ni—N2	2.0964 (13)	N2—C2	1.445 (2)
Ni—Cl1^i	2.4635 (4)	C4—C3	1.393 (3)
Ni—Cl1	2.4635 (4)	C4—C5	1.392 (3)
N1—C1	1.446 (2)	C2—C3	1.394 (2)
N1^i—Ni—N1	180.0	Cl1^i—Ni—Cl1	180.0
N1^i—Ni—N2^i	81.64 (5)	C1—N1—Ni	108.34 (10)
N1—Ni—N2^i	98.36 (5)	C6—C1—C2	119.71 (15)
N1^i—Ni—N2	98.36 (5)	C6—C1—N1	122.80 (15)
N1—Ni—N2	81.64 (5)	C2—C1—N1	117.39 (14)
N2^i—Ni—N2	180.00 (6)	C5—C6—C1	120.26 (17)
N1^i—Ni—Cl1^i	92.01 (4)	C2—N2—Ni	108.09 (10)
N1—Ni—Cl1^i	87.99 (4)	C3—C4—C5	120.11 (17)
N2^i—Ni—Cl1^i	90.75 (4)	C3—C2—C1	119.80 (16)
N2—Ni—Cl1^i	89.25 (4)	C3—C2—N2	122.55 (15)
N1^i—Ni—Cl1	87.99 (4)	C1—C2—N2	117.53 (14)
N1—Ni—Cl1	92.01 (4)	C4—C3—C2	120.14 (17)
N2^i—Ni—Cl1	89.25 (4)	C6—C5—C4	119.97 (18)
N2—Ni—Cl1	90.75 (4)

Symmetry code: (i) −x, −y, −z+1.