INFLUENCE OF THE HOST LATTICE ON THE PHOTOLUMINESCENCE OF NI2-XCSXCAF3 AND RBCA1-XCDXF3 CRYSTALS( IONS IN RB1)

The optical properties of Ni2+ doped Rb1-xCsxCaF3 and RbCa1-xCdxF3 sol id solutions were studied. The T-1(2g)(D-1)-->(3)A(2g)(F-3) and T-1(2g )(D-1)-->T-3(2g)(F-3) emission bands and the lifetime of the T-1(2g) l evel were measured as a function of the crystal composition. Both the band positions and the lifetime show a monotonic change with x between the values corresponding to the pure crystals. In Rb1-xCsxCaF3 crysta ls the contributions of different Ni2+ centers in the emission bands w ere resolved. The shift of emissions is due to the Rb+-Cs+ substitutio n as next nearest neighbors of Ni2+ ions as well as to a change of the lattice parameter with the composition of solid solutions. Both contr ibutions were separated for some of the Ni2+ centers. (C) 1997 America n Institute of Physics.