Electron spin resonance studies of copper-doped dipiperidyl- and tetramethyl-thiouram disulphides

Abstract

Single-crystal e.s.r. studies are reported for copper–doped dipiperidylthiouram disulphide (Cu–dptd) and tetramethylthiouram disulphide (Cu-tmtd). Results for the former can be interpreted in terms of D_2h, point symmetry about Cu²⁺, being similar to copper-doped dithiocarbamates. Cu–tmtd on the other hand appears to be one of the rare cases of Cu²⁺ in predominantly tetrahedral co-ordination. Unusually small hyperfine interaction constants then arise from 3d⁸4p hybridisation which is allowed under tetrahedral symmetry.