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Title: Modeling Optical Spectra of Large Organic Systems Using Real-Time Propagation of Semiempirical Effective Hamiltonians

Abstract

We present an implementation of a time-dependent semiempirical method (INDO/S) in NWChem using real-time (RT) propagation to address, in principle, the entire spectrum of valence electronic excitations. Adopting this model, we study the UV-visible spectra of medium-sized systems like P3B2, f-coronene, and in addition much larger systems like ubiquitin in the gas phase and the betanin chromophore in the presence of two explicit solvents (water and methanol). RT-INDO/S provides qualitatively and indeed often quantitatively accurate results when compared with RT- TDDFT or experimental spectra. While demonstrated here for INDO/S in particular, our implementation provides a framework for performing electron dynamics in large systems using semiempirical Hartree-Fock (HF) Hamiltonians in general.

Authors:
ORCiD logo [1];  [2]; ORCiD logo [1]; ORCiD logo [1];  [2]
  1. Department of Chemistry, Chemical Theory Center, and Supercomputing Institute, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455-0431, United States
  2. Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99338, United States
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1398179
Report Number(s):
PNNL-SA-126881
Journal ID: ISSN 1549-9618; 49640; KC0301060
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Theory and Computation; Journal Volume: 13; Journal Issue: 9
Country of Publication:
United States
Language:
English
Subject:
Environmental Molecular Sciences Laboratory

Citation Formats

Ghosh, Soumen, Andersen, Amity, Gagliardi, Laura, Cramer, Christopher J., and Govind, Niranjan. Modeling Optical Spectra of Large Organic Systems Using Real-Time Propagation of Semiempirical Effective Hamiltonians. United States: N. p., 2017. Web. doi:10.1021/acs.jctc.7b00618.
Ghosh, Soumen, Andersen, Amity, Gagliardi, Laura, Cramer, Christopher J., & Govind, Niranjan. Modeling Optical Spectra of Large Organic Systems Using Real-Time Propagation of Semiempirical Effective Hamiltonians. United States. doi:10.1021/acs.jctc.7b00618.
Ghosh, Soumen, Andersen, Amity, Gagliardi, Laura, Cramer, Christopher J., and Govind, Niranjan. 2017. "Modeling Optical Spectra of Large Organic Systems Using Real-Time Propagation of Semiempirical Effective Hamiltonians". United States. doi:10.1021/acs.jctc.7b00618.
@article{osti_1398179,
title = {Modeling Optical Spectra of Large Organic Systems Using Real-Time Propagation of Semiempirical Effective Hamiltonians},
author = {Ghosh, Soumen and Andersen, Amity and Gagliardi, Laura and Cramer, Christopher J. and Govind, Niranjan},
abstractNote = {We present an implementation of a time-dependent semiempirical method (INDO/S) in NWChem using real-time (RT) propagation to address, in principle, the entire spectrum of valence electronic excitations. Adopting this model, we study the UV-visible spectra of medium-sized systems like P3B2, f-coronene, and in addition much larger systems like ubiquitin in the gas phase and the betanin chromophore in the presence of two explicit solvents (water and methanol). RT-INDO/S provides qualitatively and indeed often quantitatively accurate results when compared with RT- TDDFT or experimental spectra. While demonstrated here for INDO/S in particular, our implementation provides a framework for performing electron dynamics in large systems using semiempirical Hartree-Fock (HF) Hamiltonians in general.},
doi = {10.1021/acs.jctc.7b00618},
journal = {Journal of Chemical Theory and Computation},
number = 9,
volume = 13,
place = {United States},
year = 2017,
month = 8
}
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