Single-crystal electron spin resonance spectra of tris(diethyldithiocarbamato)oxomolybdenum(V) and chlorobis(diethyldithiocarbamato)oxomolybdenum(V) diluted in isomorphous host lattices

Abstract

Room-temperature single-crystal e.s.r. spectra are reported for [MoO(S₂CNEt₂)₃] diluted in the corresponding niobium compound, and for [MoOCl(S₂CNEt₂)₂] diluted in [MoO₂(S₂CNEt₂)₂]. The principal molecular parameters for [MoO(S₂CNEt₂)₃] are g₁= 1.970 ± 0.001, g₂= 1.978 ± 0.001, g₃= 1.985 ± 0.001, A₁= 56.9 ± 0.2 × 10^–4 cm^–1, A₂= 33.6 ± 0.2 × 10^–4 cm^–1, and A₃= 27.1 ± 0.2 × 10^–4 cm^–1, whilst those for [MoOCl(S₂CNEt₂)₂] are g₁= 1.945 ± 0.001, g₂= 1.958 ± 0.001, g₃= 1.984 ± 0.001, A₁(Mo)= 24.1 ± 0.2 × 10^–4 cm^–1, A₂(Mo)= 27.5 ± 0.2 × 10^–4 cm^–1, A₃(Mo)= 61.4 ± 0.4 × 10^–4 cm^–1, |A₁(Cl)|= 2.6 ± 0.1 × 10^–4 cm^–1, |A₂(Cl)|= 4.5 ± 0.1 × 10^–4 cm^–1, and |A₃(Cl)|= 12.6 ± 0.1 × 10^–4 cm^–1. In both compounds the principal axis systems for the g and metal hyperfine tensors are non-coincident. The electronic absorption spectra and angular variation of the single-crystal g values have been interpreted in terms of a parameterised angular-overlap model.