Novel photoisomerization behavior of Rh binuclear complexes involving an azobenzene-bridged bis(terpyridine) ligand. Strong effects of counterion and solvent and the induction of redox potential shift.

Abstract

Rhodium dinuclear complexes containing azobenzene-bridged bis(terpyridine), tpy−AB−tpy, were synthesized, and their trans-to-cis photoisomerization behavior was examined. The photoisomerization rate depends on the size of the counterion and the polarity and viscosity of the solvent. In electrochemical measurements, the reduction potential due to Rh(III)/Rh(I) of the cis form of the complex was shifted in a negative direction from the trans form.