LOCAL LATTICE STRUCTURE, CRYSTAL-FIELD AND ENERGY-LEVEL PATTERNS IN CSCDBR3-TM3+ CRYSTALS

In CsCdBr3, Tm3+ substitutes for Cd2+. It predominately forms symmetri c dimer centers and single-ion centers, both of trigonal symmetry. The energy level schemes of both centers were determined by EPR and site- selective laser spectroscopy. To describe the spectra term dependent c rystal-field parameters were deduced on the basis of a microscopic mod el taking into account the local lattice deformation induced by the im purity centers and the quasi-resonant virtual scattering of intrinsic lattice excitations by the Tm3+ ions. (C) 1998 Elsevier Science S.A.