Electron spin resonance spectra of a TiIV–TiIII mixed-valence tetranuclear species [Ti4(OR)12O]

Abstract

Reduction of [Ti(OPrⁱ)₄] by Li[BH₄] at room temperature produces the mixed-valence complex [Ti₄(OPrⁱ)₁₂O] which has been shown by variable-temperature e.s.r. measurements to contain Ti^III and Ti^IV. The complex is tetranuclear in the solid state, while dinuclear species are observed in solution. The solid complex exhibits singlet–triplet states arising from the interaction between two Ti^III atoms. The various transitions ΔM₈= 1 as well as ΔM₈= 2 have been observed.