CAJ | 학술논문

通过偏振拉曼光谱和第一性原理计算对非线性光学晶体BaBPO5的晶格振动模式进行了研究.实验得到了不同几何配置下、在100—1600 cm?1范围内的晶体偏振拉曼光谱与傅里叶变换红外吸收谱,结合因子群分析方法研究了晶体的外振动与内振动模式特征.分析表明拉曼振动主要来自于PO4四面体和BO4四面体的振动,且PO4基团振动具有较强的拉曼与红外活性.此外,根据第一性原理对晶体拉曼振动进行了数值模拟,进一步明确了拉曼峰与晶体中原子振动的对应关系,计算表明拉曼光谱中位于672 cm?1峰位来自晶体中B—O—P键的伸缩振动,这是晶体中PO4四面体和BO4四面体共顶点连接的特征结构在光谱中的体现.
통과편진랍만광보화제일성원리계산대비선성광학정체BaBPO5적정격진동모식진행료연구.실험득도료불동궤하배치하、재100—1600 cm?1범위내적정체편진랍만광보여부리협변환홍외흡수보,결합인자군분석방법연구료정체적외진동여내진동모식특정.분석표명랍만진동주요래자우PO4사면체화BO4사면체적진동,차PO4기단진동구유교강적랍만여홍외활성.차외,근거제일성원리대정체랍만진동진행료수치모의,진일보명학료랍만봉여정체중원자진동적대응관계,계산표명랍만광보중위우672 cm?1봉위래자정체중B—O—P건적신축진동,저시정체중PO4사면체화BO4사면체공정점련접적특정결구재광보중적체현.
In this paper, the lattice vibrational modes of the nonlinear optical crystal BaBPO5 are studied using polarized Raman spectrum and the first-principles calculation. The polarized Raman spectra are obtained in different configurations and recorded in a range of 100–1600 cm?1. Combining the experimental data of the FT-IR spectrum, the lattice vibrational modes of the internal and external vibrations are analyzed by the factor group analysis method. The results indicate that the primary Raman peaks of the BaBPO5 crystal are ascribed to the internal vibrations of the PO4 and BO4 tetrahedrons, and the vibrations of the PO4 tetrahedron show strong Raman-and IR-activity. On the other hand, the first-principles calculation indicates the correlation of the vibrational modes with the atomic activities. Especially, the Raman peak located at 672 cm?1 is ascribed to the vibration of the B–O–P bond, which is the connector between the PO4 and BO4 tetrahedron. These results obtained in this work are important for understanding the micro-structures of the BaBPO5 crystal, and the further study on the crystal growth mechanism.