Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270102010430/ta1380sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270102010430/ta1380Isup2.hkl |
CCDC reference: 193398
Compound (I) was synthesized according to the literature method of Davison & Holm (1967). Single crystals of (I) suitable for X-ray analysis were grown by vapour diffusion of pentane into a dichloromethane solution of the compound.
Data collection: CrystalClear (Molecular Structure Corporation & Rigaku Corporation, 2001); cell refinement: CrystalClear; data reduction: CrystalStructure (Molecular Structure Corporation & Rigaku Corporation, 2001; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: CRYSTALS (Watkin et al., 1996); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: CrystalStructure.
(C16H36N)2[Co(C4N2S2)2]2 | F(000) = 2448 |
Mr = 1163.52 | Dx = 1.374 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.7107 Å |
a = 29.457 (4) Å | Cell parameters from 7543 reflections |
b = 14.060 (2) Å | θ = 1.6–13.7° |
c = 14.703 (2) Å | µ = 0.93 mm−1 |
β = 112.518 (5)° | T = 90 K |
V = 5625.2 (14) Å3 | Prism, black |
Z = 4 | 0.3 × 0.3 × 0.2 mm |
Rigaku Mercury CCD area-detector diffractometer | 4718 reflections with F2 > 2σ(F2) |
Detector resolution: 14.62 pixels mm-1 | Rint = 0.050 |
ω scans | θmax = 27.5° |
Absorption correction: analytical (de Meulenaer & Tompa, 1965) | h = −37→38 |
Tmin = 0.827, Tmax = 0.830 | k = −18→13 |
21339 measured reflections | l = −19→19 |
6176 independent reflections |
Refinement on F2 | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.045 | Weighting scheme based on measured s.u.'s w = 1/σ2(Fo2) |
wR(F2) = 0.067 | (Δ/σ)max < 0.001 |
S = 1.44 | Δρmax = 0.48 e Å−3 |
4749 reflections | Δρmin = −0.52 e Å−3 |
343 parameters |
(C16H36N)2[Co(C4N2S2)2]2 | V = 5625.2 (14) Å3 |
Mr = 1163.52 | Z = 4 |
Monoclinic, C2/c | Mo Kα radiation |
a = 29.457 (4) Å | µ = 0.93 mm−1 |
b = 14.060 (2) Å | T = 90 K |
c = 14.703 (2) Å | 0.3 × 0.3 × 0.2 mm |
β = 112.518 (5)° |
Rigaku Mercury CCD area-detector diffractometer | 6176 independent reflections |
Absorption correction: analytical (de Meulenaer & Tompa, 1965) | 4718 reflections with F2 > 2σ(F2) |
Tmin = 0.827, Tmax = 0.830 | Rint = 0.050 |
21339 measured reflections |
R[F2 > 2σ(F2)] = 0.045 | 343 parameters |
wR(F2) = 0.067 | H-atom parameters constrained |
S = 1.44 | Δρmax = 0.48 e Å−3 |
4749 reflections | Δρmin = −0.52 e Å−3 |
Refinement. Refinement using reflections with F2 > 2.0 σ(F2). The weighted R-factor (wR) and goodness of fit (S) are based on F2. R-factor (gt) are based on F. The threshold expression of F2 > 2.0 σ(F2) is used only for calculating R-factor (gt). |
x | y | z | Uiso*/Ueq | ||
Co | 0.013000 (10) | 0.43129 (3) | 0.43045 (3) | 0.01125 (9) | |
S1 | 0.02318 (2) | 0.58522 (5) | 0.44991 (5) | 0.0120 (2) | |
S2 | 0.08942 (2) | 0.40651 (5) | 0.53106 (5) | 0.0137 (2) | |
S3 | −0.05077 (2) | 0.46157 (5) | 0.29644 (5) | 0.0128 (2) | |
S4 | 0.00555 (2) | 0.27876 (5) | 0.40032 (5) | 0.0143 (2) | |
N5 | 0.15918 (7) | 0.9093 (2) | 0.0802 (2) | 0.0108 (5) | |
N3 | −0.16020 (9) | 0.3463 (2) | 0.1147 (2) | 0.0229 (7) | |
N4 | −0.08676 (8) | 0.1012 (2) | 0.2597 (2) | 0.0178 (6) | |
N1 | 0.12491 (8) | 0.7651 (2) | 0.5526 (2) | 0.0193 (6) | |
N2 | 0.20616 (9) | 0.5364 (2) | 0.6644 (2) | 0.0234 (7) | |
C13 | 0.18286 (9) | 0.8190 (2) | 0.0630 (2) | 0.0118 (7) | |
C22 | 0.08261 (9) | 1.0102 (2) | −0.0132 (2) | 0.0150 (7) | |
C14 | 0.23019 (9) | 0.7904 (2) | 0.1460 (2) | 0.0157 (7) | |
C23 | 0.03346 (9) | 1.0057 (2) | −0.1007 (2) | 0.0180 (7) | |
C15 | 0.24573 (11) | 0.6925 (2) | 0.1266 (2) | 0.0204 (8) | |
C17 | 0.19216 (10) | 0.9950 (2) | 0.0892 (2) | 0.0142 (7) | |
C21 | 0.11087 (9) | 0.9194 (2) | −0.0084 (2) | 0.0124 (6) | |
C18 | 0.20605 (10) | 1.0141 (2) | 0.0018 (2) | 0.0175 (7) | |
C1 | 0.08605 (9) | 0.5979 (2) | 0.5176 (2) | 0.0126 (7) | |
C10 | 0.12307 (10) | 0.8145 (2) | 0.1852 (2) | 0.0146 (7) | |
C2 | 0.11360 (9) | 0.5183 (2) | 0.5530 (2) | 0.0125 (7) | |
C6 | 0.16541 (10) | 0.5279 (2) | 0.6149 (2) | 0.0156 (7) | |
C3 | −0.07578 (10) | 0.3508 (2) | 0.2605 (2) | 0.0140 (7) | |
C7 | −0.12267 (10) | 0.3468 (2) | 0.1792 (2) | 0.0152 (7) | |
C4 | −0.05140 (9) | 0.2703 (2) | 0.3055 (2) | 0.0132 (7) | |
C8 | −0.07137 (9) | 0.1767 (2) | 0.2785 (2) | 0.0135 (7) | |
C19 | 0.23540 (10) | 1.1065 (2) | 0.0157 (2) | 0.0206 (8) | |
C9 | 0.15048 (9) | 0.9029 (2) | 0.1758 (2) | 0.0135 (7) | |
C11 | 0.11506 (10) | 0.8122 (2) | 0.2813 (2) | 0.0155 (7) | |
C5 | 0.10706 (9) | 0.6909 (2) | 0.5372 (2) | 0.0139 (7) | |
C12 | 0.08396 (10) | 0.7266 (2) | 0.2842 (2) | 0.0202 (8) | |
C24 | 0.00476 (10) | 1.0968 (2) | −0.1133 (2) | 0.0224 (8) | |
C16 | 0.29103 (10) | 0.6559 (2) | 0.2093 (2) | 0.0225 (8) | |
C20 | 0.28614 (11) | 1.1013 (2) | 0.0977 (3) | 0.0339 (9) | |
H1 | 0.02305 | 1.1477 | −0.1248 | 0.0258* | |
H2 | −0.02570 | 1.0908 | −0.1677 | 0.0258* | |
H3 | −0.00116 | 1.1092 | −0.0552 | 0.0259* | |
H4 | 0.28471 | 0.6514 | 0.2679 | 0.0263* | |
H5 | 0.29926 | 0.5948 | 0.1925 | 0.0261* | |
H6 | 0.31760 | 0.6984 | 0.2196 | 0.0263* | |
H7 | 0.28295 | 1.0872 | 0.1582 | 0.039* | |
H8 | 0.30477 | 1.0527 | 0.0833 | 0.039* | |
H9 | 0.30238 | 1.1606 | 0.1030 | 0.039* | |
H10 | 0.07907 | 0.7266 | 0.3444 | 0.0245* | |
H11 | 0.05305 | 0.7299 | 0.2306 | 0.0242* | |
H12 | 0.10037 | 0.6698 | 0.2794 | 0.0241* | |
H13 | 0.15997 | 0.7686 | 0.0527 | 0.0140* | |
H14 | 0.18967 | 0.8277 | 0.0055 | 0.0140* | |
H15 | 0.25520 | 0.8350 | 0.1505 | 0.0182* | |
H16 | 0.22526 | 0.7896 | 0.2062 | 0.0182* | |
H17 | 0.21947 | 0.6494 | 0.1175 | 0.0236* | |
H18 | 0.25231 | 0.6950 | 0.0683 | 0.0235* | |
H19 | 0.11794 | 0.9159 | −0.0661 | 0.0138* | |
H20 | 0.09036 | 0.8676 | −0.0074 | 0.0136* | |
H21 | 0.07698 | 1.0175 | 0.0459 | 0.0169* | |
H22 | 0.10107 | 1.0628 | −0.0209 | 0.0171* | |
H23 | 0.03942 | 0.9942 | −0.1588 | 0.0204* | |
H24 | 0.01459 | 0.9550 | −0.0906 | 0.0203* | |
H25 | 0.17561 | 1.0497 | 0.0990 | 0.0160* | |
H26 | 0.22164 | 0.9856 | 0.1452 | 0.0164* | |
H27 | 0.22545 | 0.9627 | −0.0052 | 0.0212* | |
H28 | 0.17696 | 1.0190 | −0.0559 | 0.0212* | |
H29 | 0.23919 | 1.1207 | −0.0442 | 0.0252* | |
H30 | 0.21744 | 1.1560 | 0.0306 | 0.0252* | |
H31 | 0.18153 | 0.9036 | 0.2291 | 0.0159* | |
H32 | 0.13198 | 0.9569 | 0.1797 | 0.0155* | |
H33 | 0.09198 | 0.8130 | 0.1320 | 0.0180* | |
H34 | 0.14155 | 0.7600 | 0.1822 | 0.0179* | |
H35 | 0.14601 | 0.8084 | 0.3347 | 0.0175* | |
H36 | 0.09871 | 0.8688 | 0.2870 | 0.0173* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Co | 0.0102 (2) | 0.0101 (2) | 0.0141 (2) | 0.0004 (2) | 0.0054 (2) | −0.0002 (2) |
S1 | 0.0106 (3) | 0.0108 (3) | 0.0149 (3) | 0.0001 (3) | 0.0050 (3) | 0.0011 (3) |
S2 | 0.0110 (3) | 0.0108 (3) | 0.0184 (4) | 0.0016 (3) | 0.0048 (3) | 0.0004 (3) |
S3 | 0.0133 (3) | 0.0123 (3) | 0.0135 (3) | 0.0005 (3) | 0.0058 (3) | 0.0011 (3) |
S4 | 0.0131 (3) | 0.0115 (3) | 0.0174 (4) | 0.0013 (3) | 0.0050 (3) | −0.0012 (3) |
N5 | 0.0098 (11) | 0.0111 (11) | 0.0091 (11) | −0.0001 (9) | 0.0010 (9) | −0.0020 (9) |
N3 | 0.022 (1) | 0.024 (1) | 0.0173 (13) | −0.0020 (11) | 0.0024 (12) | −0.0013 (11) |
N4 | 0.0150 (12) | 0.0188 (13) | 0.0189 (13) | 0.0004 (10) | 0.0057 (10) | −0.0013 (10) |
N1 | 0.0181 (13) | 0.0168 (13) | 0.0209 (13) | −0.0011 (11) | 0.0051 (11) | 0.0017 (10) |
N2 | 0.016 (1) | 0.021 (1) | 0.027 (1) | 0.0022 (11) | 0.0018 (12) | −0.0021 (11) |
C13 | 0.0111 (13) | 0.0098 (13) | 0.0140 (13) | 0.0012 (11) | 0.0041 (11) | −0.0011 (11) |
C22 | 0.013 (1) | 0.013 (1) | 0.016 (1) | 0.0033 (11) | 0.0026 (11) | −0.0003 (11) |
C14 | 0.0122 (13) | 0.015 (1) | 0.018 (1) | 0.0004 (11) | 0.0038 (11) | −0.0023 (11) |
C23 | 0.015 (1) | 0.020 (2) | 0.016 (1) | 0.0040 (12) | 0.0022 (12) | −0.0003 (12) |
C15 | 0.023 (2) | 0.016 (2) | 0.019 (2) | 0.0062 (13) | 0.0050 (13) | 0.0007 (12) |
C17 | 0.0130 (13) | 0.0103 (13) | 0.018 (1) | −0.0007 (11) | 0.0040 (11) | 0.0004 (11) |
C21 | 0.0126 (13) | 0.013 (1) | 0.0091 (12) | −0.0025 (11) | 0.0008 (11) | −0.0008 (11) |
C18 | 0.018 (1) | 0.017 (2) | 0.018 (2) | −0.0019 (12) | 0.0078 (12) | −0.0012 (12) |
C1 | 0.0132 (13) | 0.0146 (13) | 0.0099 (13) | 0.0007 (11) | 0.0044 (11) | 0.0015 (11) |
C10 | 0.015 (1) | 0.014 (1) | 0.016 (1) | −0.0009 (11) | 0.0071 (12) | −0.0029 (11) |
C2 | 0.0108 (13) | 0.016 (1) | 0.0133 (13) | −0.0015 (11) | 0.0072 (11) | −0.0016 (11) |
C6 | 0.017 (2) | 0.013 (1) | 0.017 (1) | 0.0017 (12) | 0.0073 (13) | −0.0007 (11) |
C3 | 0.017 (1) | 0.016 (1) | 0.012 (1) | −0.0008 (12) | 0.0086 (12) | −0.0019 (11) |
C7 | 0.019 (2) | 0.013 (1) | 0.017 (2) | −0.0004 (12) | 0.0106 (13) | 0.0010 (11) |
C4 | 0.0138 (13) | 0.014 (1) | 0.0137 (13) | 0.0002 (11) | 0.0076 (11) | −0.0020 (11) |
C8 | 0.0117 (13) | 0.016 (1) | 0.013 (1) | 0.0030 (11) | 0.0056 (11) | 0.0010 (11) |
C19 | 0.019 (2) | 0.017 (1) | 0.027 (2) | −0.0014 (12) | 0.0100 (13) | 0.0043 (13) |
C9 | 0.0141 (13) | 0.014 (1) | 0.0113 (13) | 0.0017 (11) | 0.0039 (11) | −0.0013 (11) |
C11 | 0.017 (1) | 0.017 (1) | 0.0104 (13) | 0.0034 (12) | 0.0019 (11) | 0.0015 (11) |
C5 | 0.0121 (13) | 0.017 (1) | 0.012 (1) | 0.0029 (12) | 0.0040 (11) | 0.0027 (11) |
C12 | 0.023 (2) | 0.023 (2) | 0.014 (1) | −0.0010 (13) | 0.0071 (12) | 0.0027 (12) |
C24 | 0.018 (2) | 0.026 (2) | 0.020 (2) | 0.0081 (13) | 0.0041 (13) | 0.0039 (13) |
C16 | 0.017 (1) | 0.022 (2) | 0.026 (2) | 0.0068 (13) | 0.0050 (13) | 0.0068 (13) |
C20 | 0.022 (2) | 0.033 (2) | 0.041 (2) | −0.013 (2) | 0.006 (2) | 0.006 (2) |
Co—S1 | 2.1886 (8) | C15—H17 | 0.950 |
Co—S2 | 2.1969 (8) | C15—H18 | 0.950 |
Co—S3 | 2.1812 (8) | C17—H25 | 0.950 |
Co—S4 | 2.1839 (8) | C17—H26 | 0.950 |
S1—C1 | 1.744 (3) | C21—H19 | 0.950 |
S2—C2 | 1.705 (3) | C21—H20 | 0.950 |
S3—C3 | 1.718 (3) | C18—H27 | 0.950 |
S4—C4 | 1.727 (3) | C18—H28 | 0.950 |
N3—C7 | 1.148 (3) | C10—H33 | 0.950 |
N4—C8 | 1.147 (3) | C10—H34 | 0.950 |
N1—C5 | 1.151 (3) | C19—H29 | 0.950 |
N2—C6 | 1.147 (3) | C19—H30 | 0.950 |
C1—C2 | 1.363 (4) | C9—H31 | 0.950 |
C1—C5 | 1.427 (4) | C9—H32 | 0.950 |
C2—C6 | 1.453 (4) | C11—H35 | 0.950 |
C3—C7 | 1.440 (4) | C11—H36 | 0.950 |
C3—C4 | 1.367 (4) | C12—H10 | 0.950 |
C4—C8 | 1.434 (4) | C12—H11 | 0.950 |
Co—Coi | 3.1150 (8) | C12—H12 | 0.950 |
Co—S1i | 2.3916 (8) | C24—H1 | 0.950 |
C13—H13 | 0.950 | C24—H2 | 0.950 |
C13—H14 | 0.950 | C24—H3 | 0.950 |
C22—H21 | 0.950 | C16—H4 | 0.950 |
C22—H22 | 0.950 | C16—H5 | 0.950 |
C14—H15 | 0.950 | C16—H6 | 0.950 |
C14—H16 | 0.950 | C20—H7 | 0.950 |
C23—H23 | 0.950 | C20—H8 | 0.950 |
C23—H24 | 0.950 | C20—H9 | 0.950 |
S1—Co—S2 | 90.87 (3) | C22—C21—H19 | 107.86 |
S1—Co—S3 | 87.28 (3) | N5—C21—H20 | 107.86 |
S2—Co—S3 | 160.94 (3) | C22—C21—H20 | 107.84 |
S1—Co—S4 | 174.69 (3) | C17—C18—H27 | 109.08 |
S2—Co—S4 | 88.76 (3) | C19—C18—H27 | 109.06 |
S3—Co—S4 | 91.35 (3) | C17—C18—H28 | 109.07 |
Co—S1—C1 | 103.79 (9) | C19—C18—H28 | 109.08 |
Co—S2—C2 | 103.14 (9) | C9—C10—H33 | 108.76 |
Co—S3—C3 | 102.74 (9) | C11—C10—H33 | 108.76 |
Co—S4—C4 | 102.84 (9) | C9—C10—H34 | 108.77 |
N5—C13—H13 | 107.96 | C11—C10—H34 | 108.75 |
C14—C13—H13 | 107.97 | C18—C19—H29 | 108.48 |
N5—C13—H14 | 107.96 | C20—C19—H29 | 108.46 |
C14—C13—H14 | 107.97 | C18—C19—H30 | 108.47 |
C23—C22—H21 | 109.50 | C20—C19—H30 | 108.47 |
C21—C22—H21 | 109.50 | N5—C9—H31 | 108.17 |
C23—C22—H22 | 109.50 | C10—C9—H31 | 108.18 |
C21—C22—H22 | 109.48 | N5—C9—H32 | 108.18 |
C13—C14—H15 | 109.34 | C10—C9—H32 | 108.18 |
C15—C14—H15 | 109.34 | C10—C11—H35 | 109.19 |
C13—C14—H16 | 109.33 | C12—C11—H35 | 109.20 |
C15—C14—H16 | 109.33 | C10—C11—H36 | 109.19 |
C22—C23—H23 | 108.85 | C12—C11—H36 | 109.19 |
C24—C23—H23 | 108.83 | C11—C12—H10 | 109.47 |
C22—C23—H24 | 108.83 | C11—C12—H11 | 109.47 |
C24—C23—H24 | 108.84 | C11—C12—H12 | 109.47 |
C14—C15—H17 | 108.50 | C23—C24—H1 | 109.46 |
C16—C15—H17 | 108.50 | C23—C24—H2 | 109.47 |
C14—C15—H18 | 108.49 | C23—C24—H3 | 109.46 |
C16—C15—H18 | 108.50 | C15—C16—H4 | 109.46 |
N5—C17—H25 | 107.83 | C15—C16—H5 | 109.46 |
C18—C17—H25 | 107.84 | C15—C16—H6 | 109.47 |
N5—C17—H26 | 107.84 | C19—C20—H7 | 109.46 |
C18—C17—H26 | 107.84 | C19—C20—H8 | 109.47 |
N5—C21—H19 | 107.87 | C19—C20—H9 | 109.47 |
Symmetry code: (i) −x, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | (C16H36N)2[Co(C4N2S2)2]2 |
Mr | 1163.52 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 90 |
a, b, c (Å) | 29.457 (4), 14.060 (2), 14.703 (2) |
β (°) | 112.518 (5) |
V (Å3) | 5625.2 (14) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.93 |
Crystal size (mm) | 0.3 × 0.3 × 0.2 |
Data collection | |
Diffractometer | Rigaku Mercury CCD area-detector diffractometer |
Absorption correction | Analytical (de Meulenaer & Tompa, 1965) |
Tmin, Tmax | 0.827, 0.830 |
No. of measured, independent and observed [F2 > 2σ(F2)] reflections | 21339, 6176, 4718 |
Rint | 0.050 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.045, 0.067, 1.44 |
No. of reflections | 4749 |
No. of parameters | 343 |
No. of restraints | ? |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.48, −0.52 |
Computer programs: CrystalClear (Molecular Structure Corporation & Rigaku Corporation, 2001), CrystalClear, CrystalStructure (Molecular Structure Corporation & Rigaku Corporation, 2001, SHELXS97 (Sheldrick, 1997), CRYSTALS (Watkin et al., 1996), ORTEP-3 (Farrugia, 1997), CrystalStructure.
Co—S1 | 2.1886 (8) | N1—C5 | 1.151 (3) |
Co—S2 | 2.1969 (8) | N2—C6 | 1.147 (3) |
Co—S3 | 2.1812 (8) | C1—C2 | 1.363 (4) |
Co—S4 | 2.1839 (8) | C1—C5 | 1.427 (4) |
S1—C1 | 1.744 (3) | C2—C6 | 1.453 (4) |
S2—C2 | 1.705 (3) | C3—C7 | 1.440 (4) |
S3—C3 | 1.718 (3) | C3—C4 | 1.367 (4) |
S4—C4 | 1.727 (3) | C4—C8 | 1.434 (4) |
N3—C7 | 1.148 (3) | Co—Coi | 3.1150 (8) |
N4—C8 | 1.147 (3) | Co—S1i | 2.3916 (8) |
S1—Co—S2 | 90.87 (3) | S3—Co—S4 | 91.35 (3) |
S1—Co—S3 | 87.28 (3) | Co—S1—C1 | 103.79 (9) |
S2—Co—S3 | 160.94 (3) | Co—S2—C2 | 103.14 (9) |
S1—Co—S4 | 174.69 (3) | Co—S3—C3 | 102.74 (9) |
S2—Co—S4 | 88.76 (3) | Co—S4—C4 | 102.84 (9) |
Symmetry code: (i) −x, −y+1, −z+1. |
1,3-Dithiolato complexes of transition metals are planar electron acceptors, which have received attention in connection with their magnetic and electrical conducting properties. Molecular conductors based on extended 1,3-dithiolato complexes have received special attention recently (Kobayashi et al., 1999, 2001; Moriyama et al., 2001). Further, the discovery of ferromagnetic ordering in (NH4)[Ni(mnt)2]·H2O below 4.5 K (Coomber et al., 1996) has especially stimulated interest in [M(mnt)2]-based compounds (mnt is S2C4N22-, dimercaptomaleodinitrilato). In addition, [M(mnt)2]n- anions have been used as motifs for supramolecular assembly, taking advantage of their variation in molecular stereochemistry and formal charges (Lewis & Dance, 2000). Among the [M(mnt)2] salts, however, examples of Co complexes are fewer than those incorporating Ni, Pd or Pt ions. We report here the crystal structure of the title compound, (nBu4N)[Co(mnt)2], (I), at 90 K. \sch
Several examples of [Co(mnt)2]n- salts have been reported, involving the [Co(mnt)2]- monoanion (Fettouchi et al., 1995; Rodrigues et al., 1994; Zürcher et al., 1998), the [Co(mnt)2]2- dianion (Fallon et al., 1997; Fettouchi et al., 1995), and the mixed-valence [Co(mnt)2]3- anion (Gama et al., 1993; Lam et al., 1995). The monoanion tends to afford an antiferromagnetically interacting dimer, while the dianion often exists in the form of a monomer, showing alternate stacking with counter-cations. The structure of a 1:2 salt, (nBu4N)2[Co(mnt)2], has also been reported (Forrester et al., 1964).
Fig. 1 shows the molecular structre of (I). The [Co(mnt)2] units form discrete dimers and the components of the dimer are related to each other by a centre of symmetry located between the two metal centres. The metal atom has a distorted square-pyramidal coordination geometry and is displaced by 0.231 (1) Å from the least-squares plane defined by the four S atoms of the basal ligand. The dihedral angle between the Co/S1/S2 and Co/S3/S4 planes is ca 19.9°. Factors affecting the displacement of the metal atom from the ligand plane in [M(mnt)2]n- anions have been discussed by Alvarez et al. (1985).
The important intramolecular and intradimer distances and angles in the anion are listed in Table 1. The coordination distances are virtually identical to those of other [Co(mnt)2]- salts (Fettouchi et al., 1995). The long molecular axes of the anions are parallel, being in a slipped configuration such that the central metal atom is coordinated by the S atom of the adjacent anion, with a Co···S distance of 2.3916 (8) Å, which is somewhat longer than the four basal Co—S distances. The intradimer Co···Co distance is 3.1150 (8) Å. In contrast with the square-pyramidal [CoIII(mnt)2]- anion of (I), the dianion of [CoII(mnt)2]2- is planar, showing D2 h geometry (Forrester et al., 1964). The intramolecular distances show significant differences, depending on the formal charges on the anion.
The packing in (I) is illustrated in Fig. 2. The [Co(mnt)2]22- dimers are stacked in a columnar fashion along the c axis. The dimer units are stacked such that the long axes of adjacent dimers make an angle of ca 71° with each other. The metal atom of one dimer unit sits 3.923 (1) Å above atom S3i of the adjacent dimer unit [symmetry code: (i) -x, 1 - y, 1 - z]. There is also an S3···S3i contact distance of 3.734 (1) Å between the dimers. The interdimer Co···Co distance is 5.063 (1) Å.
The anion columns in (I) are surrounded by the tetrabutylammonium cations. Three of the nBu groups in the cation adopt the all-trans conformation, but one terminal group, C19—C20, adopts a gauche conformation. Presumably, this occurs to reduce steric hindrance between adjacent counter-cations, which have mutual contacts at these ends along the b direction.
The corresponding NiIII complex (Mochida et al., 2000) crystallizes in the same space group (C2/c), and shows similar cell parameters to those of (I). In the NiIII complex, the anions are arranged in the form of a weakly interacting dimer, and the cell volume is larger than that for the CoIII complex, by 6.5%.