Raman-active modes of a-GeSe2 and a-GeS2:: A first-principles study
Raman-active modes of a-GeSe2 and a-GeS2:: A first-principles study
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DOI：
10.1103/physrevb.60.r14985
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发表时间：
1999-12-01
影响因子：
3.7
通讯作者：
Pederson, MR
中科院分区：
文献类型：
--
作者：
Jackson, K;Briley, A;Pederson, MR
我们利用最近发展的基于密度泛函理论的计算技术研究了非晶GeSe2和GeS2的拉曼活性模式。从第一性原理直接计算了三种玻璃团块的振动模式和相关的拉曼活度。计算出的对称-拉伸模式在星团模型中的位置与观测光谱中的明显特征非常吻合。此外，基于聚类结果的模拟光谱与实验结果吻合较好，反映了光谱中键拉伸区的所有观测特征。该星团的结果为GexS1-x家族富锗样品光谱中出现的250 cm（-1）模式提供了一种新的解释。[s0163 - 1829(99) 51846 - 8]。
We have used a recently developed computational technique based on density-functional theory to study the Raman-active modes of amorphous GeSe2 and GeS2. Vibrational modes and the associated Raman activities for three cluster building blocks of the glasses are calculated directly from first principles. The positions of the calculated symmetric-stretch modes in the cluster models ape in excellent agreement with sharp features in the observed spectra. Moreover, simulated spectra based on the cluster results are in good agreement with experiment, accounting for all the observed features in the bond-stretch region of the spectra. The cluster results suggest a new interpretation for the 250 cm(-1) mode appearing in the spectra of Ge-rich samples in the GexS1-x family. [S0163-1829(99)51846-8].