Dissecting energy level renormalization and polarizability enhancement of molecules at surfaces with subsystem TDDFT
Dissecting energy level renormalization and polarizability enhancement of molecules at surfaces with subsystem TDDFT
复制标题
使用 TDDFT 子系统剖析表面分子的能级重整化和极化率增强
DOI：
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
M. Pavanello
中科院分区：
文献类型：
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作者：
Alina Umerbekova;Shoufeng Zhang;Sudheer Kumar P.;M. Pavanello
摘要
在扩展系统（如金属表面）附近的分子以特殊的方式行为。它们的能级被加宽，分子性质被大大增强，以至于它们几乎不像孤立分子的性质。这是由于动态相互作用（即，耦合激发电子态的相互作用）之间的分子，有限的系统和扩展的，无限的系统。自量子力学早期以来，费米黄金法则一直被用来解释一些动力学相互作用（如能级的加宽）。然而，这些系统的完全量子力学和从头算模型仍然难以捉摸，在很大程度上是由于模拟中的计算复杂性。在这项工作中，我们提出了子系统的含时DFT（TDDFT）模拟水和苯分子与二硫化钼单层和Au（111）表面的相互作用。超系统响应函数在分子和表面响应方面的多体展开使我们能够解剖和描述动力学相互作用。我们不仅计算并清楚地确定与耗散，加宽和峰移相关的术语，而且我们还提供了子系统TDDFT和费米黄金法则之间的连接。这项工作为子系统TDDFT模拟的接口相关的能源材料和非绝热动力学在这样的接口。
Abstract
Molecules in the vicinity of extended systems, such as metal surfaces, behave in peculiar ways. Their energy levels are broadened, and their molecular properties are so profoundly enhanced that they hardly resemble the ones of the isolated molecule. This is due to dynamical interactions (i.e., interactions that couple excited electronic states) between the molecular, finite system and the extended, infinite system. Since the early days of quantum mechanics, Fermi golden rule has been employed to explain some of the dynamical interactions (such as the broadening of the energy levels). However, a fully quantum-mechanical and ab initio model of these systems remains elusive, in most part due to the computational complexity entailed in the simulations. In this work, we present subsystem time-dependent DFT (TDDFT) simulations of water and benzene molecules as they interact with surfaces of MoS2 monolayer and Au(111). A many-body expansion of the supersystem response function in terms of molecule and surface responses allows us to dissect and describe the dynamical interactions. Not only do we compute and clearly identify terms related to dissipation, broadening, and peak shift, but we also provide a connection between subsystem TDDFT and Fermi golden rule. This work sets the stage for subsystem TDDFT simulations of interfaces relevant to energy materials and nonadiabatic dynamics at such interfaces.