The symmetric quasi-classical model using on-the-fly time-dependent density functional theory within the Tamm–Dancoff approximation
The symmetric quasi-classical model using on-the-fly time-dependent density functional theory within the Tamm–Dancoff approximation
复制标题
DOI：
10.1080/00268976.2022.2153761
复制
发表时间：
2022-09
影响因子：
1.7
通讯作者：
J. Talbot;M. Head‐Gordon;Stephen J. Cotton
中科院分区：
文献类型：
--
作者：
J. Talbot;M. Head‐Gordon;Stephen J. Cotton
在模拟非绝热从头计算分子动力学时，主要的计算挑战是用分子大小计算电子结构的不利计算成本。简单的电子结构理论，如Tamm-Dancoff近似下的含时密度泛函理论(TDDFT/TDA)，对于在现实时间尺度上模拟的中等大小的分子系统来说，减轻了这一成本。尽管TDDFT/TDA在精度上确实有一些局限性，但一个吸引人的特点是，除了通过使用密度泛函来包括电子关联之外，即使对于中等大小的基组，计算解析核梯度和非绝热耦合矢量的成本通常在计算上也是可行的。本文讨论和分析了TDDFT/TDA作为对称准经典Meyer-Miller模型(SQC/MM)的“后端”电子结构方法的一些优点和局限性。为了考察TDDFT/TDA方法的优点和局限性，采用SQC/MM方法对一个典型的丙二醛激发态氢转移过程进行了预测和分析。然后，模拟了硒的开环动力学，突出了TDDFT/TDA的一些不足之处。此外，还提出了一些新的算法，以加快一组激发电子态的解析核梯度和非绝热耦合矢量的计算。图形摘要
The primary computational challenge when simulating nonadiabatic ab initio molecular dynamics is the unfavourable compute costs of electronic structure calculations with molecular size. Simple electronic structure theories, like time-dependent density functional theory within the Tamm–Dancoff approximation (TDDFT/TDA), alleviate this cost for moderately sized molecular systems simulated on realistic time scales. Although TDDFT/TDA does have some limitations in accuracy, an appealing feature is that, in addition to including electron correlation through the use of a density functional, the cost of calculating analytic nuclear gradients and nonadiabatic coupling vectors is often computationally feasible even for moderately sized basis sets. In this work, some of the benefits and limitations of TDDFT/TDA are discussed and analysed with regard to its applicability as a ‘back-end’ electronic structure method for the symmetric quasi-classical Meyer–Miller model (SQC/MM). In order to investigate the benefits and limitations of TDDFT/TDA, SQC/MM is employed to predict and analyse a prototypical example of excited-state hydrogen transfer in gas-phase malonaldehyde. Then, the ring-opening dynamics of selenophene are simulated, which highlight some of the deficiencies of TDDFT/TDA. Additionally, some new algorithms are proposed that speed up the calculation of analytic nuclear gradients and nonadiabatic coupling vectors for a set of excited electronic states. GRAPHICAL ABSTRACT