Polavarapu Prasad L
Department of Chemistry, Vanderbilt University, Nashville, Tennessee 37235, USA.
J Phys Chem A. 2005 Aug 18;109(32):7013-23. doi: 10.1021/jp0524328.
The Kramers-Kronig (KK) transform method for deriving optical rotatory dispersion (ORD) from electronic circular dichroism (ECD) has been analyzed. Three different numerical integration methods for the KK transform have been evaluated, and the method proposed by Ohta and Ishida has been used for further calculations. Using this method, the quantum mechanical predictions of electronic circular dichroism (ECD) have been converted to corresponding ORD and compared with that derived from the linear response method. For three molecules exhibiting monosignate ORD in the nonresonant long wavelength region, the KK transform of ECD associated with the lowest energy electronic transition is found to give ORD values close to those obtained with the linear response method. For molecules exhibiting bisignate ORD in the nonresonant long wavelength region, the KK transform method may not provide the correct results. In the resonant region, the KK transform method provides a computationally economical alternative for predicting ORD. While the KK transform method works much like sum-over-states method for ORD, the former offers convenience in transforming the experimental ECD spectrum without the need for spectral curve fitting.
对用于从电子圆二色性（ECD）推导旋光色散（ORD）的克莱默斯-克勒尼希（KK）变换方法进行了分析。评估了KK变换的三种不同数值积分方法，并采用了大和田和石田提出的方法进行进一步计算。使用该方法，已将电子圆二色性（ECD）的量子力学预测转换为相应的ORD，并与从线性响应方法得出的结果进行了比较。对于在非共振长波长区域呈现单峰ORD的三个分子，发现与最低能量电子跃迁相关的ECD的KK变换给出的ORD值接近用线性响应方法获得的值。对于在非共振长波长区域呈现双峰ORD的分子，KK变换方法可能无法提供正确结果。在共振区域，KK变换方法为预测ORD提供了一种计算上经济的替代方法。虽然KK变换方法在预测ORD方面的工作方式与态叠加方法非常相似，但前者在转换实验ECD光谱时提供了便利，无需进行光谱曲线拟合。
