Bi_2ZnOB_2O_6单晶偏振拉曼光谱

Polarized Raman spectra of single crystal Bi_2ZnOB_2O_6

本文通过分析不同几何配置下的偏振拉曼光谱对非线性光学晶体的晶格振动模式进行了研究.首先根据因子群分析,将晶体的振动模按晶体对称群的不可约表示进行分类,其次测量了晶体在10—1600 cm 1范围内,不同几何配置下的偏振拉曼光谱,并在此基础上指认了晶体的晶格振动模式.300 cm 1以下的振动峰,归结为晶体的外振动,来自[BiO6],[ZnO4],[BO4]和[BO3]原子基团的平动和转动;300cm 1以上为晶体的内振动,主要与Bi-O,和Zn-O键振动有关.晶体拉曼光谱中最高振动频率达到1407 cm 1,被指认为[BO3]三角形中B-O键的伸缩振动,体现了[BO3]基团中高的电子非局域化程度.

Polarized Raman spectra of single crystal Bi2ZnOB2O6 have been recorded in the spectral range 10–1600 cm-1 at room temperature. Factor group analysis was used to obtain the normal modes of vibration of the crystal. The Raman peaks under 300 cm-1 are assigned to external modes, which are related to the rotational and transitional movement of the [BiO6], [ZnO4], [BO4] and [BO3] groups. Compared with the vibrational spectra of the compounds referred, the satisfactory assignment of most of the high-energy modes to vibrations of Bi-O, B-O and Zn-O bonds can be achieved. In particular, the Raman high-frequency peak located at 1407 cm-1 is attributed to the B-O vibration in the [BO3] triangle.