The luminescence characterization and structure of Eu2+ doped LiMgPO4.

An Eu(2+)-doped LiMgPO(4) phosphor was prepared by a high temperature solid-state reaction. The formation was confirmed by x-ray powder diffraction measurements to be a single LiMgPO(4) phase. The photoluminescence excitation and emission spectra were investigated. The luminescence shows a broad emission from the 4f(6)5d → 4f(7)(8)S7/2) transition at room temperature. At low temperature the zero-phonon line for transitions to the 4f(7) ((8)S(7/2)) level of the 4f(6)(7)Fj)5d1 excited state is observed at 360 nm and it is found that the emission line of the 4f(7)(6)P7/2) → 4f(7)(8)S7/2) transition overlaps the zero-phonon line at nearly the same position of 360 nm. The influences of temperature on the luminescence spectra and decay times were investigated. The doping mechanism of Eu(2+) ions in LiMgPO(4) was discussed. The Eu(2+) ions were suggested to occupy the Li(+) sites in LiMgPO(4) to induce the small crystal field splitting and weak nephelauxetic effect.