Near and Above Ionization Electronic Excitations with NonHermitian RealTime TimeDependent Density Functional Theory
Abstract
We present a realtime timedependent density functional theory (RTTDDFT) prescription for capturing near and postionization excitations based on nonHermitian von Neumann density matrix propagation with atomcentered basis sets, tuned rangeseparated DFT, and a phenomenological imaginary molecular orbitalbased absorbing potential to mimic coupling to the continuum. The computed extreme ultraviolet absorption spectra for acetylene (C2H2), water (H2O), and Freon 12 (CF2Cl2) agree well with electron energy loss spectroscopy (EELS) data over the range 0 to 50 eV. The absorbing potential removes spurious high energy finite basis artifacts, yielding correct bound to bound transitions, metastable (autoionizing) resonance states, and consistent overall absorption shapes.
 Authors:
 Publication Date:
 Research Org.:
 Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 1114891
 Report Number(s):
 PNNLSA97859
47703; KC0301020
 DOE Contract Number:
 AC0576RL01830
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Theory and Computation, 9(11):49394946
 Country of Publication:
 United States
 Language:
 English
 Subject:
 Density Functional Theory; electronic; excitations; ultraviolet; absorption; NonHermitian; Environmental Molecular Sciences Laboratory
Citation Formats
Lopata, Kenneth A., and Govind, Niranjan. Near and Above Ionization Electronic Excitations with NonHermitian RealTime TimeDependent Density Functional Theory. United States: N. p., 2013.
Web. doi:10.1021/ct400569s.
Lopata, Kenneth A., & Govind, Niranjan. Near and Above Ionization Electronic Excitations with NonHermitian RealTime TimeDependent Density Functional Theory. United States. doi:10.1021/ct400569s.
Lopata, Kenneth A., and Govind, Niranjan. Tue .
"Near and Above Ionization Electronic Excitations with NonHermitian RealTime TimeDependent Density Functional Theory". United States.
doi:10.1021/ct400569s.
@article{osti_1114891,
title = {Near and Above Ionization Electronic Excitations with NonHermitian RealTime TimeDependent Density Functional Theory},
author = {Lopata, Kenneth A. and Govind, Niranjan},
abstractNote = {We present a realtime timedependent density functional theory (RTTDDFT) prescription for capturing near and postionization excitations based on nonHermitian von Neumann density matrix propagation with atomcentered basis sets, tuned rangeseparated DFT, and a phenomenological imaginary molecular orbitalbased absorbing potential to mimic coupling to the continuum. The computed extreme ultraviolet absorption spectra for acetylene (C2H2), water (H2O), and Freon 12 (CF2Cl2) agree well with electron energy loss spectroscopy (EELS) data over the range 0 to 50 eV. The absorbing potential removes spurious high energy finite basis artifacts, yielding correct bound to bound transitions, metastable (autoionizing) resonance states, and consistent overall absorption shapes.},
doi = {10.1021/ct400569s},
journal = {Journal of Chemical Theory and Computation, 9(11):49394946},
number = ,
volume = ,
place = {United States},
year = {Tue Nov 12 00:00:00 EST 2013},
month = {Tue Nov 12 00:00:00 EST 2013}
}

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