Preparation of Octabromoditechnetate(III,II), [Tc₂Br₈]^3- and the Vibronic Structure of the δ → δ* Transition

Abstract

The dinstinct vibronic structure of the δ → δ* transition of Cs3[Tc2Br8] with its mixed valence is well resolved at 6 K. The electronic origin at about 5970 cm-1 is split into four components, each giving rise to progressions entirely assignable in terms of nν1 and nν1 + ν2 up to n = 9, utilizing the totally symmetric stretching modes ν1(TcTc) and ν2(TcBr) exclusively.