Metal-ligand bonding in six-coordinate d-block complexes probed by luminescence spectroscopy at variable pressure

Abstract

Luminescence spectra measured at variable pressure can reveal unique insight on ground- and emitting state properties of transition metal compounds. This chapter summarizes illustrative results for chromium(III) complexes with the d3 electron configuration and oxo complexes of rhenium(V) and molybdenum(IV) with the d2 configuration. Their luminescence transitions only involve electronic configuration changes within the t2 (O point group) molecular orbitals, leading to narrow spin-flip bands and broad bands with vibronic structure for the chromium(III) and metal-oxo complexes, respectively.