Unexpected photoluminescence from Mn2+ in LiZnNbO4

Abstract In this paper the synthesis of the LiNbZnO4 doped with Mn2+ by solid state method and its photoluminescence results are presented. The structural analysis was performed by X-ray diffraction and Rietveld refinement, while the emission of the impurity ion into this structure was investigated by photoluminescence and excitation measurements. The photoluminescence spectrum presented a broad band centered at 700 nm, associated to the transition of Mn2+ from the excited state 4T1 (4G) to the 6A1(6S) fundamental state. Crystal field parameter Dq and Racah parameters B and C were estimated using the transition energies observed in the excitation spectrum. Photoluminescence results indicate that the emission is related to an unexpected octahedral site occupation of Mn2+ in the LiZnNbO4 lattice.