Crystal lattice effects on the electronic spectrum of the manganate ion

Abstract

The polarised electronic spectra of MnO₄^2– doped into crystals of Rb₂SO₄, Cs₂SO₄, and K₂CrO₄ have been recorded at 4·2 K in the range 10 000–40 000 cm^–1. The different polarisation behaviour of the low-symmetry components of the ²T₂ terms derived from the ligand-field and charge-transfer configurations is ascribed to differences in the magnitude of the spin-orbit interaction in the two types of configuration. From an analysis of the phonon sidebands in the ligand-field spectrum, comments are made about the phonon spectra of the host lattices. Shifts in the ligand-field and charge-transfer origins on changing the host lattice are also discussed.