Crystal and molecular structures of dichloromethane-solvated tris(morpholinocarbodithioato)-complexes of chromium(III), manganese(III), and rhodium(III). Comparison of co-ordination spheres

Abstract

The title complexes [(I)–(III)] are nearly isomorphous with the known cobalt(III) analogue (IV). The principal differences between (I)–(III) arise from the nature of the central metal atoms, packing and other effects being essentially the same. They may be considered as trigonally distorted octahedral, with an approximate three-fold rotation axis. The manganese complex (II) deviated most significantly from this model, with elongated bonds in the z and slightly elongated bonds along the x direction, which can only be attributed to Jahn–Teller effects. The MS₆ co-ordination sphere is highly symmetrical in the chromium complex(I), as expected for the ⁴A ground-state, even more so than in (IV). The mean increase in metal-ligand bond distance from Co^III to Rh^III, with identical d₆(¹A₁) configurations, is very close to 0.1 Å. The ‘bite’ angle of the bidentate ligand appears to be determined largely by M–L distance.

Crystal data: (I), space group P, Z= 2, a= 13.255(9), b= 10.642(5), c= 11.395(1)Å, α= 115.16(4), β= 104.4(1), γ= 100.19(6)°, R= 4.3%, 2 218 reflections; (II), space group P, a= 13.067(3), b= 10.824(6), c= 11.475(5)Å, α= 116.23(5), β= 104.06(3), γ= 100.19(4)°. R 4.0%, 2 062 reflections; (III), space group. PZ= 2, a= 13.343(4), b= 10.596(1), c= 11.191 (1)Å, α= 114.20(1), β= 103.18(2), γ= 101.29(2)°. R 4.3% 3 529 reflections.