Bis[4-(dimethyl­amino)pyridinium] bis­(1,2-dicyano­ethyl­ene-1,2-dithiol­ato-κ²S,S′)nickelate(II)

The asymmetric unit of the title ion-pair complex, (C₇H₁₁N₂)₂[Ni(C₄N₂S₂)₂] or (DMAPH)₂[Ni(mnt)₂] [where DMAPH is 4-(dimethyl­amino)pyridinium and mnt is maleonitrile­dithiol­ate], consists of one cation and one half-anion, the Ni^II atom lying on a crystallographic centre of symmetry. The metal is coordinated by four S atoms of two mnt²⁻ ligands in a square-planar geometry. The [Ni(mnt)₂]²⁻ anions (A) and DMAPH⁺ cations (C) are stacked in an ACCA arrangement to form one-dimensional columns along the a axis, with a centroid–centroid separation between the pyridine rings of 4.032 (4) Å. The columns are linked by inter­molecular N—H...N hydrogen bonds, resulting in a two-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 291 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.028
• wR factor = 0.079
• Data-to-parameter ratio = 18.4

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Ni1    -   S2      ..       7.02 su
PLAT371_ALERT_2_C Long   C(sp2)-C(sp1) Bond  C1     -   C4     ...       1.43 Ang.
PLAT371_ALERT_2_C Long   C(sp2)-C(sp1) Bond  C2     -   C3     ...       1.43 Ang.

Alert level G
PLAT794_ALERT_5_G Check Predicted Bond Valency for Ni1         (3)       2.79

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   3 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

The syntheses, crystal structures and properties of maleonitriledithiolate (mnt^2-) transition metal complexes have received much attention in many areas such as non-linear optics and magnetic and conducting materials [Robertson & Cronin, 2002]. The introduction of some organic cations was recognized to be a powerful strategy to tune the stacking pattern of the Ni(mnt)₂ dianion in order to obtain molecular materials with unusual magnetic properties.

The asymmetric unit of the title compound consists of one DMAPH⁺ cation (DMAPH is 4-dimethylaminopyridinium) and one half-anion of formula Ni(mnt)₂^2- (mnt is 1,2-dicyanoethylene-1,2-dithiolate or maleonitriledithiolate). The nickel(II) metal, which lies on a crystallographic centre of symmetry, is coordinated by four S atoms from two mnt ligands in a square planar geometry (Fig. 1). The five-membered chelating ring is essentially planar (maximum displacement 0.019 (2) Å for atom C2). The conformations of anion and cation are similar to those observed in the corresponding copper(II) complex (Zhou & Ren, 2006). The Ni(mnt)₂ anions (A) and DMAPH⁺ cations (C) are stacked in a ACCA arrangement to form one-dimensional columns along the a axis, with a centroid···centroid separation between the pyridine rings of 4.032 (4) Å. The columns are linked by intermolecular N—H···N hydrogen bonds (Table 1) resulting in a two-dimensional network (Fig. 2).

Related literature

For general background, see: Robertson & Cronin (2002). For a related structure, see: (Zhou & Ren, 2006).

S2. Experimental

The title compound was prepared by the direct reaction of NiCl₂.6H₂O (1 mmol, 0.24 g), Na₂mnt (2 mmol, 0.37 g) and 4-dimethylaminopyridinium chloride (2 mmol, 0.32 g) in water (60 ml). Red block-shaped single crystals were obtained by slow evaporation of a CH₃CN solution at room temperature for about two weeks.

S3. Refinement

The pyridinium H atom was located in a difference Fourier map and refined freely. All other H atoms were placed in geometrically calculated positions with C—H = 0.93–0.96 Å, and refined using the riding atom approximation, with U_iso(H) = 1.2 U_eq(C) or 1.5 U_eq(C) for the methyl groups.

Computing details

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2000); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. The molecular structure of the title compound, with atom-labelling scheme and 30% probability displacement ellipsoids. H atoms are omitted for clarity. Atoms labelled with the suffix A are generated by the symmetry operator (-x, -y, -z).
	Fig. 2. A perspective view of the crystal packing of the title compound viewed along the a axis. H atoms are omitted for clarity.

Bis[4-(dimethylamino)pyridinium] bis(1,2-dicyanoethylene-1,2-dithiolato-κ²S,S')nickelate(II)

Crystal data

(C7H11N2)2[Ni(C4N2S2)2]	F(000) = 604
Mr = 585.43	Dx = 1.523 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 4341 reflections
a = 14.1631 (12) Å	θ = 2.7–29.3°
b = 6.5833 (6) Å	µ = 1.12 mm^−1
c = 15.0751 (13) Å	T = 291 K
β = 114.771 (1)°	Block, red
V = 1276.27 (19) Å^3	0.46 × 0.40 × 0.15 mm
Z = 2

Data collection

Bruker SMART APEX CCD diffractometer	3075 independent reflections
Radiation source: fine-focus sealed tube	2744 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.015
φ and ω scans	θmax = 28.0°, θmin = 2.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004)	h = −10→18
Tmin = 0.628, Tmax = 0.851	k = −8→8
8238 measured reflections	l = −19→15

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)] = 0.028	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.079	w = 1/[σ^2(Fo^2) + (0.0471P)^2 + 0.1627P] where P = (Fo^2 + 2Fc^2)/3
S = 1.08	(Δ/σ)max = 0.001
3075 reflections	Δρmax = 0.37 e Å^−3
167 parameters	Δρmin = −0.24 e Å^−3
0 restraints	Extinction correction: SHELXTL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0060 (8)

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

	x	y	z	Uiso*/Ueq
Ni1	0.0000	0.0000	0.0000	0.03144 (10)
S1	0.09496 (3)	0.27334 (6)	0.03137 (3)	0.04174 (12)
S2	0.11660 (3)	−0.16103 (6)	0.12276 (3)	0.04267 (12)
C1	0.20511 (11)	0.2056 (2)	0.13333 (11)	0.0355 (3)
C2	0.21416 (12)	0.0182 (2)	0.17392 (11)	0.0360 (3)
C3	0.30409 (13)	−0.0369 (2)	0.25921 (12)	0.0423 (4)
C4	0.28715 (12)	0.3503 (2)	0.17446 (12)	0.0418 (3)
N1	0.35347 (13)	0.4638 (2)	0.20822 (13)	0.0602 (4)
N2	0.37520 (13)	−0.0796 (3)	0.32811 (12)	0.0621 (4)
C5	0.57111 (14)	0.1127 (3)	−0.10347 (14)	0.0569 (5)
H5	0.5327	0.1986	−0.1550	0.068*
C6	0.66305 (13)	0.1782 (3)	−0.03421 (13)	0.0484 (4)
H6	0.6866	0.3081	−0.0385	0.058*
C7	0.72351 (12)	0.0507 (2)	0.04465 (11)	0.0382 (3)
C8	0.68034 (14)	−0.1433 (3)	0.04575 (14)	0.0486 (4)
H8	0.7159	−0.2338	0.0961	0.058*
C9	0.58738 (15)	−0.1975 (3)	−0.02630 (16)	0.0572 (5)
H9	0.5602	−0.3252	−0.0244	0.069*
C10	0.88001 (16)	−0.0288 (3)	0.18988 (14)	0.0552 (5)
H10A	0.8451	−0.0643	0.2302	0.083*
H10B	0.9447	0.0368	0.2290	0.083*
H10C	0.8932	−0.1495	0.1612	0.083*
C11	0.85807 (15)	0.3081 (3)	0.11201 (15)	0.0578 (5)
H11A	0.8942	0.3057	0.0705	0.087*
H11B	0.9056	0.3447	0.1771	0.087*
H11C	0.8028	0.4060	0.0876	0.087*
H4	0.472 (2)	−0.107 (4)	−0.1457 (19)	0.094 (9)*
N3	0.81502 (10)	0.1083 (2)	0.11314 (10)	0.0425 (3)
N4	0.53422 (12)	−0.0721 (3)	−0.09962 (13)	0.0596 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.02752 (15)	0.03259 (15)	0.03065 (15)	−0.00072 (9)	0.00868 (11)	0.00233 (9)
S1	0.0343 (2)	0.0353 (2)	0.0432 (2)	−0.00337 (14)	0.00413 (16)	0.00727 (15)
S2	0.0382 (2)	0.0373 (2)	0.0404 (2)	−0.00338 (15)	0.00455 (16)	0.00841 (15)
C1	0.0302 (7)	0.0374 (7)	0.0356 (7)	0.0001 (6)	0.0104 (6)	−0.0025 (6)
C2	0.0303 (7)	0.0400 (8)	0.0336 (7)	0.0018 (5)	0.0093 (6)	−0.0005 (5)
C3	0.0384 (8)	0.0399 (7)	0.0416 (9)	0.0033 (6)	0.0099 (7)	−0.0001 (6)
C4	0.0357 (8)	0.0403 (8)	0.0417 (8)	0.0008 (6)	0.0085 (6)	0.0020 (6)
N1	0.0455 (9)	0.0502 (8)	0.0626 (10)	−0.0107 (7)	0.0007 (7)	0.0012 (7)
N2	0.0491 (9)	0.0626 (10)	0.0536 (9)	0.0113 (8)	0.0008 (7)	0.0056 (8)
C5	0.0447 (9)	0.0711 (13)	0.0450 (9)	0.0119 (9)	0.0092 (8)	0.0012 (8)
C6	0.0460 (9)	0.0480 (9)	0.0476 (9)	0.0029 (7)	0.0162 (7)	0.0034 (7)
C7	0.0358 (8)	0.0428 (7)	0.0380 (8)	−0.0001 (6)	0.0174 (6)	−0.0031 (6)
C8	0.0459 (9)	0.0437 (8)	0.0549 (10)	−0.0032 (7)	0.0198 (8)	−0.0002 (7)
C9	0.0496 (10)	0.0505 (10)	0.0726 (13)	−0.0114 (8)	0.0267 (10)	−0.0149 (9)
C10	0.0484 (10)	0.0668 (12)	0.0411 (9)	0.0072 (8)	0.0095 (8)	0.0001 (8)
C11	0.0544 (11)	0.0585 (11)	0.0591 (11)	−0.0190 (9)	0.0224 (9)	−0.0131 (9)
N3	0.0368 (7)	0.0470 (7)	0.0401 (7)	−0.0027 (6)	0.0126 (5)	−0.0033 (6)
N4	0.0366 (8)	0.0743 (11)	0.0589 (10)	−0.0031 (8)	0.0113 (7)	−0.0196 (9)

Geometric parameters (Å, º)

Ni1—S2	2.1714 (4)	C7—N3	1.330 (2)
Ni1—S2^i	2.1714 (4)	C7—C8	1.419 (2)
Ni1—S1	2.1766 (4)	C8—C9	1.357 (3)
Ni1—S1^i	2.1766 (4)	C8—H8	0.9300
S1—C1	1.7278 (15)	C9—N4	1.332 (3)
S2—C2	1.7330 (15)	C9—H9	0.9300
C1—C2	1.359 (2)	C10—N3	1.452 (2)
C1—C4	1.428 (2)	C10—H10A	0.9600
C2—C3	1.426 (2)	C10—H10B	0.9600
C3—N2	1.138 (2)	C10—H10C	0.9600
C4—N1	1.140 (2)	C11—N3	1.453 (2)
C5—N4	1.335 (3)	C11—H11A	0.9600
C5—C6	1.354 (3)	C11—H11B	0.9600
C5—H5	0.9300	C11—H11C	0.9600
C6—C7	1.414 (2)	N4—H4	0.89 (3)
C6—H6	0.9300
S2—Ni1—S2^i	180.00 (4)	C9—C8—C7	120.37 (17)
S2—Ni1—S1	92.200 (14)	C9—C8—H8	119.8
S2^i—Ni1—S1	87.800 (14)	C7—C8—H8	119.8
S2—Ni1—S1^i	87.800 (14)	N4—C9—C8	121.51 (18)
S2^i—Ni1—S1^i	92.200 (14)	N4—C9—H9	119.2
S1—Ni1—S1^i	180.00 (2)	C8—C9—H9	119.2
C1—S1—Ni1	103.03 (5)	N3—C10—H10A	109.5
C2—S2—Ni1	103.11 (5)	N3—C10—H10B	109.5
C2—C1—C4	120.26 (13)	H10A—C10—H10B	109.5
C2—C1—S1	120.95 (12)	N3—C10—H10C	109.5
C4—C1—S1	118.78 (11)	H10A—C10—H10C	109.5
C1—C2—C3	121.12 (14)	H10B—C10—H10C	109.5
C1—C2—S2	120.69 (12)	N3—C11—H11A	109.5
C3—C2—S2	118.19 (11)	N3—C11—H11B	109.5
N2—C3—C2	179.0 (2)	H11A—C11—H11B	109.5
N1—C4—C1	179.03 (19)	N3—C11—H11C	109.5
N4—C5—C6	121.62 (18)	H11A—C11—H11C	109.5
N4—C5—H5	119.2	H11B—C11—H11C	109.5
C6—C5—H5	119.2	C7—N3—C10	121.84 (15)
C5—C6—C7	120.49 (18)	C7—N3—C11	121.77 (15)
C5—C6—H6	119.8	C10—N3—C11	116.30 (15)
C7—C6—H6	119.8	C9—N4—C5	120.39 (16)
N3—C7—C6	122.23 (15)	C9—N4—H4	120.9 (18)
N3—C7—C8	122.16 (16)	C5—N4—H4	118.6 (18)
C6—C7—C8	115.61 (15)
S2—Ni1—S1—C1	−0.14 (5)	N4—C5—C6—C7	0.4 (3)
S2^i—Ni1—S1—C1	179.86 (5)	C5—C6—C7—N3	178.82 (16)
S1—Ni1—S2—C2	0.74 (6)	C5—C6—C7—C8	−0.9 (3)
S1^i—Ni1—S2—C2	−179.26 (6)	N3—C7—C8—C9	−179.04 (17)
Ni1—S1—C1—C2	−0.76 (14)	C6—C7—C8—C9	0.7 (3)
Ni1—S1—C1—C4	179.09 (11)	C7—C8—C9—N4	0.1 (3)
C4—C1—C2—C3	1.4 (2)	C6—C7—N3—C10	−175.46 (16)
S1—C1—C2—C3	−178.76 (13)	C8—C7—N3—C10	4.3 (3)
C4—C1—C2—S2	−178.27 (12)	C6—C7—N3—C11	1.0 (2)
S1—C1—C2—S2	1.57 (19)	C8—C7—N3—C11	−179.29 (16)
Ni1—S2—C2—C1	−1.46 (14)	C8—C9—N4—C5	−0.7 (3)
Ni1—S2—C2—C3	178.86 (12)	C6—C5—N4—C9	0.4 (3)

Symmetry code: (i) −x, −y, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N4—H4···N1^ii	0.89 (3)	2.34 (3)	3.040 (2)	135 (2)

Symmetry code: (ii) x, −y+1/2, z−1/2.