Lefrancois Daniel, Tuna Deniz, Martínez Todd J, Dreuw Andreas
Interdisciplinary Center for Scientific Computing, Ruprecht-Karls University , Im Neuenheimer Feld 205, 69120 Heidelberg, Germany.
Max-Planck-Institut für Kohlenforschung , 45470 Mülheim an der Ruhr, Germany.
J Chem Theory Comput. 2017 Sep 12;13(9):4436-4441. doi: 10.1021/acs.jctc.7b00634. Epub 2017 Aug 31.
While the conventional variants of the algebraic-diagrammatic construction (ADC) scheme for the polarization propagator are generally incapable of correctly describing the topology of S/S conical intersections (CIs), its corresponding spin-flip (SF) variant of third-order ADC (ADC(3)) is herein demonstrated to successfully reproduce the S/S minimum-energy CI (MECI) of twisted formaldinium (HC═NH). Analytical nuclear excited-state gradients of ADC have been used in combination with the CIOpt program for the optimization of the MECI without the need for nonadiabatic-coupling vectors. For comparison, MS-CASPT2 calculations were performed via conventional CI optimization employing analytical nonadiabatic-coupling vectors. It is shown that SF-ADC(3) yields the correct dimensionality of the CI and overall compares very favorably to the MS-CASPT2 results.
虽然用于极化传播子的代数图形构建（ADC）方案的传统变体通常无法正确描述S/S锥形交叉点（CI）的拓扑结构，但本文证明其相应的三阶ADC（ADC(3)）的自旋翻转（SF）变体能够成功重现扭曲甲脒（HC═NH）的S/S最低能量CI（MECI）。ADC的解析核激发态梯度已与CIOpt程序结合使用，用于优化MECI，而无需非绝热耦合矢量。为作比较，通过采用解析非绝热耦合矢量的传统CI优化进行了MS-CASPT2计算。结果表明，SF-ADC(3)产生了正确的CI维度，总体上与MS-CASPT2结果相比非常有利。
