A1 Journal article (refereed)
Kohn-Sham Decomposition in Real-Time Time-Dependent Density-Functional Theory : An Efficient Tool for Analyzing Plasmonic Excitations (2017)

Rossi, T. P., Kuisma, M., Puska, M. J., Nieminen, R. M., & Erhart, P. (2017). Kohn-Sham Decomposition in Real-Time Time-Dependent Density-Functional Theory : An Efficient Tool for Analyzing Plasmonic Excitations. Journal of Chemical Theory and Computation, 13(10), 4779-4790. https://doi.org/10.1021/acs.jctc.7b00589

JYU authors or editors

Kuisma, Mikael

Publication details

All authors or editors: Rossi, Tuomas P.; Kuisma, Mikael; Puska, Martti J.; Nieminen, Risto M.; Erhart, Paul

Journal or series: Journal of Chemical Theory and Computation

ISSN: 1549-9618

eISSN: 1549-9626

Publication year: 2017

Volume: 13

Issue number: 10

Pages range: 4779-4790

Publisher: American Chemical Society

Publication country: United States

Publication language: English

DOI: https://doi.org/10.1021/acs.jctc.7b00589

Publication open access: Not open

Publication channel open access:

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/55715

Abstract

Electronic excitations can be efficiently analyzed in terms of the underlying Kohn-Sham (KS) electron-hole transitions. While such a decomposition is readily available in the linear-response time-dependent density-functional theory (TDDFT) approaches based on the Casida equations, a comparable analysis is less commonly conducted within the real-time-propagation TDDFT (RT-TDDFT). To improve this situation, we present here an implementation of a KS decomposition tool within the local-basis-set RT-TDDFT code in the free GPAW package. Our implementation is based on postprocessing of data that is readily available during time propagation, which is important for retaining the efficiency of the underlying RT-TDDFT to large systems. After benchmarking our implementation on small benzene derivatives by explicitly reconstructing the Casida eigenvectors from RT-TDDFT, we demonstrate the performance of the method by analyzing the plasmon resonances of icosahedral silver nanoparticles up to Ag561. The method provides a clear description of the splitting of the plasmon in small nanoparticles due to individual single-electron transitions as well as the formation of a distinct d-electron-screened plasmon resonance in larger nanoparticles.

Keywords: nanoparticles; plasmons; density functional theory

Free keywords: plasmonic excitations; Kohn-Sham decomposition

Fields of science: