中文摘要：

利用水平单温区管式电阻炉,合成了LiGaSe2多晶材料,并用X射线衍射（X-ray diffraction,XRD）和Raman光谱对其结构进行了表征。XRD谱表明：LiGaSe2多晶材料具有正交结构或黄铜矿结构,2种结构的多晶材料都是高纯的且结晶性良好。在合成过程中,最后阶段的恒温温度及降温速率将决定LiGaSe2的物相。通过Raman谱分析,找到2种类闪锌矿振动峰,其中低频峰与Ga—Se键的晶格振动有关,而高频峰与Li—Se键的振动有关。2种结构LiGaSe2中Li—Se键和Ga—Se键力常数存在微小差异,导致2种Raman谱谱峰发生移动。

英文摘要：

LiGaSe2 polycrystalline materials were synthesized using a one-temperature horizontal tube furnace.Their structures were characterized by the X-ray powder diffraction（XRD） and Raman spectra.The XRD results reveal that the two kinds of LiGaSe2 polycrystalline materials with orthorhombic and chalcopyrite structures are single phase and have good crystallization.It is proved that the final soaking temperature and decreasing-temperature rate determine the phase transformation of LiGaSe2.Two sphalerite-like vibration peaks were identified for Raman spectra.The low-frequency mode peaks are mainly related to Ga-Se vibrations,whereas the high-frequency mode peaks are mainly derived from Li-Se vibrations.The slight shift of peak positions in two structures is caused by the differences of force constants of Li-Se and Ga-Se bonds in the different structures.