A one-dimensional ladder-like six-coordinate cadmium polymer: catena-poly[bis­[(S)-2-methyl­piper­azine-1,4-diium] [bis­[tri­chlorido­cadmium(II)]-di-μ₃-chlorido]]

The crystal structure of the title compound {(C₅H₁₄N₂)₂[Cd₂Cl₈]}_n, (I), consists of hydrogen-bonded 2-methyl­piper­azine­diium (H₂MPPA²⁺) cations in the presence of one-dimensional polymeric {[CdCl₃(μ₃-Cl)]²⁻}_n anions. The Cd^II centres are hexa­coordinated by three terminal chlorides and three bridging chlorides and have a slightly distorted octa­hedral CdCl₃(μ₃-Cl)₃ arrangement. The alternating CdCl₆ octa­hedra form four-membered Cd₂Cl₂ rings by the sharing of neighbouring Cd–Cl edges to give rise to extended one-dimensional ladder-like chains parallel to the b axis, with a Cd...Cd distance of 4.094 (2) Å and a Cd...Cd...Cd angle of 91.264 (8)°. The H₂MPPA²⁺ cations crosslink the [CdCl₃(μ₃-Cl)]_n chains by the formation of two N—H...Cl hydrogen bonds to each chain, giving rise to one-dimensional ladder-like H₂MPPA²⁺–Cl₂ hydrogen-bonded chains [graph set R₄²(14)]. The [CdCl₃(μ₃-Cl)]_n chains are inter­woven with the H₂MPPA²⁺–Cl₂ hydrogen-bonded chains, giving rise to a three-dimensional supra­molecular network.

Computing details

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear (Rigaku, 2005); data reduction: CrystalClear (Rigaku, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

catena-Poly[bis[(S)-2-methylpiperazine-1,4-diium] [bis[trichloridocadmium(II)]-di-µ₃-chlorido]]

Crystal data

(C5H14N2)[CdCl4]	F(000) = 696
Mr = 356.38	Dx = 1.968 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 4003 reflections
a = 13.342 (7) Å	θ = 2.6–27.5°
b = 5.853 (3) Å	µ = 2.66 mm^−1
c = 15.404 (8) Å	T = 291 K
V = 1202.9 (11) Å^3	Block, colourless
Z = 4	0.36 × 0.32 × 0.30 mm

Data collection

Rigaku Mercury2 diffractometer	2758 independent reflections
Radiation source: fine-focus sealed tube	2654 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.050
Detector resolution: 13.6612 pixels mm^-1	θmax = 27.5°, θmin = 2.6°
CCD profile fitting scans	h = −17→17
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005)	k = −7→7
Tmin = 0.35, Tmax = 0.40	l = −19→19
12240 measured reflections

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F^2 > 2σ(F^2)] = 0.023	w = 1/[σ^2(Fo^2) + (0.022P)^2] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.048	(Δ/σ)max = 0.001
S = 1.01	Δρmax = 0.82 e Å^−3
2758 reflections	Δρmin = −0.57 e Å^−3
114 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.0058 (4)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), with how many Friedel pairs?
Secondary atom site location: difference Fourier map	Absolute structure parameter: −0.06 (2)

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
C1	0.6439 (2)	0.5947 (5)	0.57259 (18)	0.0335 (6)
H1	0.6716	0.7441	0.5884	0.040*
C2	0.7118 (2)	0.4106 (6)	0.60808 (17)	0.0354 (6)
H2A	0.7167	0.4264	0.6706	0.042*
H2B	0.6830	0.2620	0.5956	0.042*
C3	0.8107 (2)	0.4090 (5)	0.47352 (17)	0.0354 (6)
H3A	0.7861	0.2598	0.4561	0.043*
H3B	0.8779	0.4273	0.4506	0.043*
C4	0.74363 (19)	0.5910 (6)	0.43714 (17)	0.0337 (6)
H4A	0.7720	0.7400	0.4495	0.040*
H4B	0.7393	0.5741	0.3746	0.040*
C5	0.5386 (2)	0.5758 (9)	0.6091 (2)	0.0599 (9)
H5A	0.5113	0.4285	0.5952	0.090*
H5B	0.4972	0.6928	0.5842	0.090*
H5C	0.5407	0.5942	0.6710	0.090*
Cd1	0.893832 (13)	0.92676 (4)	0.763339 (12)	0.03140 (7)
Cl1	0.88902 (5)	0.92559 (11)	0.59419 (4)	0.02782 (12)
Cl2	0.71085 (5)	0.90735 (16)	0.77661 (5)	0.04507 (18)
Cl3	0.92925 (5)	0.92619 (13)	0.93032 (4)	0.02815 (13)
Cl4	1.08727 (4)	0.91555 (12)	0.74166 (4)	0.02624 (12)
N1	0.64182 (16)	0.5756 (5)	0.47552 (14)	0.0314 (5)
H1A	0.6134	0.4444	0.4617	0.041 (8)*
H1B	0.6119	0.6750	0.4575	0.037 (9)*
N2	0.81308 (16)	0.4241 (4)	0.56966 (13)	0.0306 (4)
H2C	0.8414	0.3201	0.5872	0.042 (10)*
H2D	0.8433	0.5511	0.5842	0.025 (7)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0380 (14)	0.0306 (14)	0.0319 (14)	0.0026 (13)	−0.0092 (11)	−0.0045 (13)
C2	0.0413 (15)	0.0330 (14)	0.0319 (14)	−0.0041 (14)	−0.0100 (11)	0.0027 (14)
C3	0.0392 (14)	0.0359 (15)	0.0311 (13)	0.0062 (15)	−0.0089 (11)	−0.0057 (13)
C4	0.0375 (14)	0.0330 (14)	0.0306 (13)	−0.0028 (14)	−0.0101 (11)	0.0063 (13)
C5	0.0441 (18)	0.085 (3)	0.050 (2)	0.004 (2)	−0.0037 (15)	−0.003 (2)
Cd1	0.02546 (10)	0.04512 (12)	0.02363 (10)	−0.00011 (10)	0.00011 (7)	0.00010 (9)
Cl1	0.0366 (3)	0.0220 (3)	0.0249 (3)	−0.0008 (4)	−0.0043 (2)	−0.0001 (3)
Cl2	0.0273 (3)	0.0614 (4)	0.0466 (4)	−0.0015 (4)	0.0026 (3)	0.0016 (4)
Cl3	0.0358 (3)	0.0225 (3)	0.0262 (3)	−0.0006 (3)	0.0023 (2)	0.0002 (3)
Cl4	0.0236 (3)	0.0309 (3)	0.0242 (3)	−0.0006 (2)	0.0001 (2)	0.0002 (3)
N1	0.0361 (11)	0.0233 (10)	0.0347 (12)	0.0038 (11)	−0.0153 (9)	0.0016 (11)
N2	0.0357 (11)	0.0240 (10)	0.0321 (11)	0.0017 (12)	−0.0149 (9)	0.0026 (11)

Geometric parameters (Å, º)

C1—N1	1.500 (3)	C5—H5A	0.9600
C1—C2	1.510 (4)	C5—H5B	0.9600
C1—C5	1.517 (4)	C5—H5C	0.9600
C1—H1	0.9800	Cd1—Cl2	2.4525 (15)
C2—N2	1.477 (4)	Cd1—Cl4	2.6032 (14)
C2—H2A	0.9700	Cd1—Cl1	2.6064 (15)
C2—H2B	0.9700	Cd1—Cl3	2.6152 (15)
C3—N2	1.484 (3)	Cd1—Cl4^i	2.8730 (16)
C3—C4	1.500 (4)	Cl4—Cd1^ii	2.8730 (16)
C3—H3A	0.9700	N1—H1A	0.8825
C3—H3B	0.9700	N1—H1B	0.7586
C4—N1	1.484 (3)	N2—H2C	0.7656
C4—H4A	0.9700	N2—H2D	0.8743
C4—H4B	0.9700
N1—C1—C2	108.6 (2)	C1—C5—H5C	109.5
N1—C1—C5	110.3 (2)	H5A—C5—H5C	109.5
C2—C1—C5	111.7 (3)	H5B—C5—H5C	109.5
N1—C1—H1	108.8	Cl2—Cd1—Cl4	175.15 (3)
C2—C1—H1	108.7	Cl2—Cd1—Cl1	93.36 (2)
C5—C1—H1	108.8	Cl4—Cd1—Cl1	84.04 (2)
N2—C2—C1	111.4 (2)	Cl2—Cd1—Cl3	95.61 (3)
N2—C2—H2A	109.4	Cl4—Cd1—Cl3	86.96 (2)
C1—C2—H2A	109.4	Cl1—Cd1—Cl3	171.00 (2)
N2—C2—H2B	109.4	Cl2—Cd1—Cl4^i	97.80 (3)
C1—C2—H2B	109.3	Cl4—Cd1—Cl4^i	86.253 (18)
H2A—C2—H2B	108.0	Cl1—Cd1—Cl4^i	88.740 (19)
N2—C3—C4	110.1 (2)	Cl3—Cd1—Cl4^i	90.67 (2)
N2—C3—H3A	109.7	Cd1—Cl4—Cd1^ii	96.63 (2)
C4—C3—H3A	109.6	C4—N1—C1	112.1 (2)
N2—C3—H3B	109.7	C4—N1—H1A	110.5
C4—C3—H3B	109.7	C1—N1—H1A	108.3
H3A—C3—H3B	108.1	C4—N1—H1B	106.8
N1—C4—C3	110.7 (2)	C1—N1—H1B	108.5
N1—C4—H4A	109.5	H1A—N1—H1B	110.6
C3—C4—H4A	109.4	C2—N2—C3	112.1 (2)
N1—C4—H4B	109.6	C2—N2—H2C	105.5
C3—C4—H4B	109.5	C3—N2—H2C	108.3
H4A—C4—H4B	108.1	C2—N2—H2D	111.4
C1—C5—H5A	109.5	C3—N2—H2D	108.4
C1—C5—H5B	109.5	H2C—N2—H2D	111.0
H5A—C5—H5B	109.5

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···Cl3^iii	0.88	2.29	3.164 (3)	169
N1—H1B···Cl3^iv	0.76	2.43	3.145 (3)	157
N2—H2C···Cl1^v	0.77	2.40	3.112 (3)	156
N2—H2D···Cl1	0.87	2.28	3.128 (3)	163

Symmetry codes: (iii) −x+3/2, −y+1, z−1/2; (iv) −x+3/2, −y+2, z−1/2; (v) x, y−1, z.