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Analysis and visualization of energy densities. I. Insights from real-time time-dependent density functional theory simulations.

ABSTRACT: In this article, we report a scheme to analyze and visualize the energy density fluctuations during the real-time time-dependent density functional theory (RT-TDDFT) simulations. Using Ag4-N2 complexes as examples, it is shown that the grid-based Kohn-Sham energy density can be computed at each time step using a procedure from Nakai and coworkers. Then the instantaneous energy of each molecular fragment (such as Ag4 and N2) can be obtained by partitioning the Kohn-Sham energy densities using Becke or fragment-based Hirshfeld (FBH) scheme. A strong orientation-dependence is observed for the energy flow between the Ag4 cluster and a nearby N2 molecule in the RT-TDDFT simulations. Future applications of such an energy density analysis in electron dynamics simulations are discussed.

SUBMITTER: Yang J

PROVIDER: S-EPMC7722154 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Analysis and visualization of energy densities. I. Insights from real-time time-dependent density functional theory simulations.

Yang Junjie J Pei Zheng Z Deng Jingheng J Mao Yuezhi Y Wu Qin Q Yang Zhibo Z Wang Bin B Aikens Christine M CM Liang Wanzhen W Shao Yihan Y

Physical chemistry chemical physics : PCCP 20201201 46

In this article, we report a scheme to analyze and visualize the energy density fluctuations during the real-time time-dependent density functional theory (RT-TDDFT) simulations. Using Ag4-N2 complexes as examples, it is shown that the grid-based Kohn-Sham energy density can be computed at each time step using a procedure from Nakai and coworkers. Then the instantaneous energy of each molecular fragment (such as Ag4 and N2) can be obtained by partitioning the Kohn-Sham energy densities using Bec ...[more]

PMID: 33170198

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Analysis and visualization of energy densities. I. Insights from real-time time-dependent density functional theory simulations.

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Analysis and visualization of energy densities. I. Insights from real-time time-dependent density functional theory simulations.

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