Decoupled coordinates for precise molecular vibrational analysis by vibrational self-consistent-field and vibrational configuration interaction methods
Decoupled coordinates for precise molecular vibrational analysis by vibrational self-consistent-field and vibrational configuration interaction methods
复制标题
通过振动自洽场和振动构型相互作用方法进行精确分子振动分析的解耦坐标
DOI：
10.1016/j.cpletx.2019.100010
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发表时间：
2019
影响因子：
--
通讯作者：
Kenro Hashimoto
中科院分区：
文献类型：
--
作者：
Hibiki Iwase;Kenro Hashimoto
用振动自组态相互作用(VSCF)和振动组态相互作用(VCI)方法建立了解耦坐标，有效地计算了精确的分子频率。利用该坐标成功地解耦了NH3中伞模和对称NH伸缩模之间的强耦合。基于新坐标计算的NH3频率与实验值符合得很好，即使在VSCF水平上也是如此，包括泛音和合成带以及隧道倍增。用解耦后的坐标计算变尺度函数的计算量比通常的法向坐标要小得多。
Decoupled coordinates were developed to calculate precise molecular frequencies effectively by the vibrational self-consisted-field (VSCF) and vibrational configuration interaction (VCI) methods. Strong coupling between the normal modes of the umbrella and symmetric NH stretching modes in NH3was successfully decoupled by using the present coordinates. The calculated frequencies of NH3based on the new coordinates agreed well with the experimental values, even at the VSCF level, including overtone and combination bands as well as tunnel doubling. The computational cost of the VSCF by the decoupled coordinates was much less than that by the usual normal coordinates.