Theory of Raman scattering and Raman optical activity: near resonance theory and levels of approximation
Theory of Raman scattering and Raman optical activity: near resonance theory and levels of approximation
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DOI：
10.1007/s00214-007-0267-9
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发表时间：
2008
影响因子：
1.7
通讯作者：
L. Nafie
中科院分区：
文献类型：
--
作者：
L. Nafie
拉曼散射和拉曼旋光性（罗阿）理论的新水平被确定在一般的非限制（GU）理论和称为近共振（NR）理论的远离共振（FFR）理论之间。在NR理论中，拉曼张量是不对称的，并且对于异相双圆偏振（DCPII）罗阿，罗阿的入射和散射圆偏振（ICP和SCP）形式与非零强度之间存在不等价性。在从GU理论到FFR理论的过程中识别了几个理论水平。NR理论通过假设激发电子态的振动能级与基态电子态的振动能级相同，提供了GU理论中存在但FFR中不存在的振动电子细节。NR理论遵守时间反演对称性，并且可以以计算上易处理的形式表示，从而相对于FFR理论提供的描述，提供了对拉曼和罗阿强度的频率依赖性的改进描述。
A new level of the theory of Raman scattering and Raman optical activity (ROA) is identified between the general, unrestricted (GU) theory and the far-from-resonance (FFR) theory called the near resonance (NR) theory. In the NR theory, the Raman tensor is not symmetric, and there is nonequivalence between the incident and scattered circular polarization (ICP and SCP) forms of ROA and non-zero intensity for out-of-phase dual circular polarization (DCPII) ROA. Several levels of theory are identified in passing from the GU theory to the FFR theory. The NR theory provides vibronic detail, present in the GU theory but absent from the FFR, by assuming that the vibrational levels of the excited electronic states are the same as those of the ground electronic state. The NR theory obeys time-reversal symmetry and can be expressed in a form that is computationally tractable, thereby providing an improved description of the frequency dependence of Raman and ROA intensities relative to that provided by the FFR theory.