Temperature dependent phonon modes and ionicity of LiGaO₂ single crystal

This paper reports that polarized far-infrared reflectivity measurements have been done on LiGaO₂ single crystal along two crystalline axes at different temperatures. The temperature dependent frequencies of the longitudinal and transverse optical phonon have been obtained from the real part of optical conductivity and the loss function respectively. A small Drude component is observed at frequency below 300 cm^ - 1 which could arise from Li ions or oxygen deficiencies. The ionicity of LiGaO₂ has been studied from the analysis of the Born effective charge of different ions.