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Title: Photoabsorption and photoionization dynamics study of silicon tetrafluoride in the framework of time-dependent density-functional theory

Abstract

Photoionization cross sections and angular distributions of silicon tetrafluoride have been calculated in the framework of the time-dependent density-functional theory approach. Both valence and inner shell ionizations have been considered in an extended photon energy range. Calculations have been carried out by using two different exchange-correlation (xc) potentials characterized by the correct asymptotic behavior. Theoretical results obtained with both the van Leeuwen-Baerends and statistical average of orbital potentials (SAOP) xc potentials are compared with photoabsorption, photoionization, and electron-scattering experiments as well as with previous theoretical calculations. It is suggested that even if both xc potentials provide a reasonably good description of the photoionization dynamics, correlation effects are phenomenologically better accounted for by the SAOP xc potential. Overall, the good accuracy attained with the linear combination of atomic orbitals-time dependent density-functional theory method in reproducing the experimental findings for SiF{sub 4} makes it a promising and powerful method for the characterization of the photoionization dynamics from medium and large-size molecules.

Authors:
 [1];  [2]; ;  [1];  [2];  [2]
  1. Dipartimento di Scienze Chimiche, Universita degli Studi di Trieste, Via L. Giorgieri 1, I-34127, Trieste (Italy)
  2. (Italy)
Publication Date:
OSTI Identifier:
20787103
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. A; Journal Volume: 73; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevA.73.042704; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; ANGULAR DISTRIBUTION; CORRELATIONS; CROSS SECTIONS; DENSITY FUNCTIONAL METHOD; ELECTRONS; INNER-SHELL IONIZATION; LCAO METHOD; MOLECULES; PHOTOIONIZATION; PHOTON-MOLECULE COLLISIONS; PHOTONS; POTENTIALS; SCATTERING; SILICON FLUORIDES; TIME DEPENDENCE; VALENCE

Citation Formats

Toffoli, D., INFM DEMOCRITOS, National Simulation Center, Trieste, Stener, M., Decleva, P., INFM DEMOCRITOS, National Simulation Center, Trieste, and Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali, INSTM, Unita di Trieste, Trieste. Photoabsorption and photoionization dynamics study of silicon tetrafluoride in the framework of time-dependent density-functional theory. United States: N. p., 2006. Web. doi:10.1103/PHYSREVA.73.0.
Toffoli, D., INFM DEMOCRITOS, National Simulation Center, Trieste, Stener, M., Decleva, P., INFM DEMOCRITOS, National Simulation Center, Trieste, & Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali, INSTM, Unita di Trieste, Trieste. Photoabsorption and photoionization dynamics study of silicon tetrafluoride in the framework of time-dependent density-functional theory. United States. doi:10.1103/PHYSREVA.73.0.
Toffoli, D., INFM DEMOCRITOS, National Simulation Center, Trieste, Stener, M., Decleva, P., INFM DEMOCRITOS, National Simulation Center, Trieste, and Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali, INSTM, Unita di Trieste, Trieste. Sat . "Photoabsorption and photoionization dynamics study of silicon tetrafluoride in the framework of time-dependent density-functional theory". United States. doi:10.1103/PHYSREVA.73.0.
@article{osti_20787103,
title = {Photoabsorption and photoionization dynamics study of silicon tetrafluoride in the framework of time-dependent density-functional theory},
author = {Toffoli, D. and INFM DEMOCRITOS, National Simulation Center, Trieste and Stener, M. and Decleva, P. and INFM DEMOCRITOS, National Simulation Center, Trieste and Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali, INSTM, Unita di Trieste, Trieste},
abstractNote = {Photoionization cross sections and angular distributions of silicon tetrafluoride have been calculated in the framework of the time-dependent density-functional theory approach. Both valence and inner shell ionizations have been considered in an extended photon energy range. Calculations have been carried out by using two different exchange-correlation (xc) potentials characterized by the correct asymptotic behavior. Theoretical results obtained with both the van Leeuwen-Baerends and statistical average of orbital potentials (SAOP) xc potentials are compared with photoabsorption, photoionization, and electron-scattering experiments as well as with previous theoretical calculations. It is suggested that even if both xc potentials provide a reasonably good description of the photoionization dynamics, correlation effects are phenomenologically better accounted for by the SAOP xc potential. Overall, the good accuracy attained with the linear combination of atomic orbitals-time dependent density-functional theory method in reproducing the experimental findings for SiF{sub 4} makes it a promising and powerful method for the characterization of the photoionization dynamics from medium and large-size molecules.},
doi = {10.1103/PHYSREVA.73.0},
journal = {Physical Review. A},
number = 4,
volume = 73,
place = {United States},
year = {Sat Apr 15 00:00:00 EDT 2006},
month = {Sat Apr 15 00:00:00 EDT 2006}
}
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