Rudolph Mark, Autschbach Jochen
Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, USA.
Chirality. 2008 Sep;20(9):995-1008. doi: 10.1002/chir.20547.
It can be computationally expensive to compute smooth, well resolved, optical rotation (OR) dispersion (ORD) curves from first principles theory. Instead of computing the OR at a large number of frequency points, similar results can be obtained by combined use of a computed circular dichroism (CD) spectrum along with a few OR calculations by using subtractive Kramers-Kronig transformations. We have tested various subtractive schemes for simulated (analytical) CD/ORD and for time-dependent density functional computations for dimethyloxirane, fenchone, and [4]triangulane. Nonresonant ORD can be obtained with as few as two OR and one CD calculation. For resonant ORD we found that between 7 and 15 OR computations plus the CD spectrum were typically sufficient, depending on the number of excitations within the frequency window of interest.
从第一性原理理论计算平滑、分辨率高的旋光（OR）色散（ORD）曲线在计算上可能成本高昂。与其在大量频率点计算旋光，通过结合计算得到的圆二色性（CD）光谱以及使用减法克喇末-克朗尼格变换进行的几次旋光计算，可以获得类似的结果。我们已经针对模拟（解析）CD/ORD以及环氧乙烷、葑酮和[4]三角烷的含时密度泛函计算测试了各种减法方案。非共振ORD只需进行两次旋光计算和一次CD计算即可获得。对于共振ORD，我们发现通常7至15次旋光计算加上CD光谱就足够了，这取决于感兴趣频率窗口内的激发次数。
