Excited state properties of diphenylmercury: photolysis and luminescence under ambient conditions

In solution HgIIPh2 undergoes a photoredox decomposition (φ=0.006 at λirr=254 nm in CH3CN) which is induced by ligand-to-metal charge transfer excitation. In the solid state this decomposition is largely prevented but a phosphorescence appears which originates from the lowest-energy ππ* (phenyl) intraligand triplet.