Theory of resonance Raman scattering. An improved formulation of the vibronic expansion method
Theory of resonance Raman scattering. An improved formulation of the vibronic expansion method
复制标题
共振拉曼散射理论。
DOI：
10.1063/1.430549
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发表时间：
1975
影响因子：
4.4
通讯作者：
W. Siebrand
中科院分区：
文献类型：
--
作者：
M. Mingardi;W. Siebrand
对多原子分子中拉曼强度的电子振动展开理论进行了重新考虑，以提高其准确性，并将其有效性扩展到共振区。几个基本的改进：（i）条款耦合绝热玻恩-奥本海默状态被证明是潜在的重要来源的拉曼强度，即使当电子能级间距是大的。(ii)传统的渐近展开的能量衰减器被取代的扩展，它仍然收敛在共振区，并允许直接求和的中间振动状态。(iii)振动线宽被证明是一个重要的参数，在理论中，并充分考虑到治疗的能量分母一贯作为一个复杂的量。所有的处理结果在解析公式表示的光谱参数。与一般光谱性质的初步比较。新的结果显示，与共振相去甚远...
The vibronic expansion theory of Raman intensities in polyatomic molecules is reconsidered so as to improve its accuracy and extend its validity into the resonance region. Several fundamental improvements are introduced: (i) Terms which couple adiabatic Born−Oppenheimer states are shown to be potentially important sources of Raman intensity even when the electronic level spacing is large. (ii) The conventional asymptotic expansion of the energy denominators is replaced by an expansion which remains convergent in the resonance region and allows direct summation over the intermediate vibrational states. (iii) The vibrational linewidth is shown to be an important parameter in the theory and is fully taken into account by treating the energy denominator consistently as a complex quantity. The over−all treatment results in analytic formulas expressed in terms of spectroscopic parameters. A preliminary comparison with general spectroscopic properties is presented. Far from resonance the new results are shown to...