Department of Chemistry, School of Natural Science, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulju-gun, Ulsan 44919, South Korea.
J Chem Theory Comput. 2023 Apr 25;19(8):2186-2197. doi: 10.1021/acs.jctc.2c00939. Epub 2023 Apr 6.
We present coupled equations of motion for correlated electron-nuclear dynamics for real-space and real-time propagation with a proper electron-nuclear correlation (ENC) from the exact factorization. Since the original ENC term from the exact factorization is non-Hermitian, the numerical instability arises as we propagate an electronic wave function. In this paper, we propose a Hermitian-type ENC term which depends on the electron density matrix and the nuclear quantum momentum. Moreover, we show that the Hermitian property of the electron-nuclear correlation term can capture quantum (de)coherence with a stable numerical real-space and real-time propagation. As an application, we demonstrate a real-space and real-time propagation of an electronic wave function coupled to trajectory-based nuclear motion for a one-dimensional model Hamiltonian. Our approach can capture nonadiabatic phenomena as well as quantum decoherence in excited state molecular dynamics. In addition, we propose a scheme to extend the current approach to many-body electronic states based on real-time time-dependent density functional theory, testing the nonadiabatic dynamics of a simple molecular system.
我们提出了用于实空间和实时传播的相关电子-核动力学的耦合运动方程，并从精确的因式分解中得到了适当的电子-核相关（ENC）。由于来自精确因式分解的原始 ENC 项是非厄米的，因此当我们传播电子波函数时会出现数值不稳定性。在本文中，我们提出了一种依赖于电子密度矩阵和核量子动量的厄米型 ENC 项。此外，我们表明电子-核相关项的厄米性质可以通过稳定的数值实空间和实时传播来捕获量子（去）相干。作为应用，我们演示了一维模型哈密顿量中电子波函数与基于轨迹的核运动的实空间和实时传播。我们的方法可以捕获非绝热现象以及激发态分子动力学中的量子退相干。此外，我们提出了一种基于实时时间相关密度泛函理论将当前方法扩展到多体电子态的方案，测试了简单分子系统的非绝热动力学。
