Wavelength dependence in the ligand field photochemistry of cobalt(III) amines

Abstract

The low quantum yield ligand field excitation photosubstitution reactions of Co(III) amine complexes are shown to be plausibly interpretable as the superposition of two component reactions. The first is an excitation wavelength-independent process which is associated with the ligand field triplet which has figured strongly in discussion of photosubstitution of the analogous Rh(III) complexes. The second is a wavelength-dependent reaction which is associated with direct reaction from the ligand field singlet. This interpretation of wavelength dependence in conjunction with recent interpretations of the picosecond transient absorption spectra suggests a unified model of the photochemistry of d/sup 6/ complexes.