Simulating Magnetic Circular Dichroism Spectra with Real-Time Time-Dependent Density Functional Theory in Gauge Including Atomic Orbitals
Simulating Magnetic Circular Dichroism Spectra with Real-Time Time-Dependent Density Functional Theory in Gauge Including Atomic Orbitals
复制标题
在包括原子轨道的规范中用实时时变密度泛函理论模拟磁圆二色光谱
DOI：
10.1021/acs.jctc.9b00632
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发表时间：
2019
影响因子：
5.5
通讯作者：
Li, Xiaosong
中科院分区：
文献类型：
--
作者：
Sun, Shichao;Beck, Ryan A.;Williams-Young, David;Li, Xiaosong
磁性圆二色性（MCD）光谱能够提供对化学系统的几何，电子和磁性的见解。然而，考虑到需要同时处理有限磁场和光场，理解和模拟它们可能具有挑战性。因此，需要有效的模拟来理解光谱和解析分子的电子状态。实时动力学被广泛应用于吸收光谱和电子圆二色性等电子光谱的模拟中，但用实时动力学模拟MCD在技术上和理论上都具有挑战性。在这项工作中，我们介绍了一个实时的动力学为基础的从头计算方法与非微扰处理的静态磁场与伦敦轨道模拟MCD光谱的封闭壳系统。磁场的影响包含在无自旋的非相对论性哈密顿量中。实时含时密度泛函理论动力学，然后进行，从中我们计算的响应函数中存在的外部磁场，给出MCD谱。本文提出的方法被用来模拟嘧啶，吡嗪和1，4-萘醌的MCD光谱。结果进行了讨论和比较的实验。
Magnetic circular dichroism (MCD) spectra are able to provide insights into the geometric, electronic, and magnetic properties of chemical systems. However, they can be challenging to understand and simulate given the need to simultaneously treat both the finite magnetic and optical fields. Thus, efficient simulations are desired to understand the spectra and resolve the molecular electronic states. Real-time dynamics are used widely in the simulation of electronic spectroscopies such as absorption as well as electronic circular dichroism, but simulating MCD with real-time dynamics is technically and theoretically challenging. In this work, we introduce a real-time dynamics-based ab initio method with a nonperturbative treatment of a static magnetic field with London orbitals for simulating the MCD spectra of closed shell systems. Effects of a magnetic field are included variationally in the spin-free nonrelativistic Hamiltonian. Real-time time-dependent density functional theory dynamics are then performed, from which we compute the response function in the presence of the external magnetic field, giving the MCD spectrum. The method developed in this paper is applied to simulate the MCD spectra for pyrimidine, pyrazine, and 1,4-naphthoquinone. Results are discussed and compared to the experiment.