ESR and PAS in vanadium-doped LaPO4

Abstract

Electron spin resonance and photoacoustic absorption spectra of vanadium-doped LaPO4 have been studied at room temperature. Two nonequivalent centres are observed. Both can be described by a spin Hamiltonian of axial symmetry. The Hamiltonian parameters are: site 1: g/sub ///=1.9280, gperpendicular to =1.9780, A/sub ///=-181*10-4 cm-1Aperpendicular to =-68*10-4 cm-1; site 2: g/sub ///=1.9070, gperpendicular to =1.9840, A/sub ///=-195*10-4 cm-1, Aperpendicular to =-81*10-4 cm-1. Analysis of ESR and PAS data suggests that both centres can be attributed to VO2+ ions and are analogous to similar centres found in phosphate glasses.