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Title: Equilibrium configurations of large nanostructures using the embedded saturated-fragments stochastic density functional theory

Authors:
 [1];  [2];  [3];  [1]
  1. Fritz Haber Center for Molecular Dynamics, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
  2. Department of Chemistry, University of California and Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA, The Raymond and Beverly Sackler Center for Computational Molecular and Materials Science, Tel Aviv University, Tel Aviv 69978, Israel
  3. Department of Chemistry, University of California, Los Angeles, California 90095, USA
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1363830
Grant/Contract Number:
AC02-05CH11232
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 146; Journal Issue: 22; Related Information: CHORUS Timestamp: 2018-02-14 11:26:13; Journal ID: ISSN 0021-9606
Publisher:
American Institute of Physics
Country of Publication:
United States
Language:
English

Citation Formats

Arnon, Eitam, Rabani, Eran, Neuhauser, Daniel, and Baer, Roi. Equilibrium configurations of large nanostructures using the embedded saturated-fragments stochastic density functional theory. United States: N. p., 2017. Web. doi:10.1063/1.4984931.
Arnon, Eitam, Rabani, Eran, Neuhauser, Daniel, & Baer, Roi. Equilibrium configurations of large nanostructures using the embedded saturated-fragments stochastic density functional theory. United States. doi:10.1063/1.4984931.
Arnon, Eitam, Rabani, Eran, Neuhauser, Daniel, and Baer, Roi. 2017. "Equilibrium configurations of large nanostructures using the embedded saturated-fragments stochastic density functional theory". United States. doi:10.1063/1.4984931.
@article{osti_1363830,
title = {Equilibrium configurations of large nanostructures using the embedded saturated-fragments stochastic density functional theory},
author = {Arnon, Eitam and Rabani, Eran and Neuhauser, Daniel and Baer, Roi},
abstractNote = {},
doi = {10.1063/1.4984931},
journal = {Journal of Chemical Physics},
number = 22,
volume = 146,
place = {United States},
year = 2017,
month = 6
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on June 14, 2018
Publisher's Accepted Manuscript

Citation Metrics:
Cited by: 2works
Citation information provided by
Web of Science

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  • We develop a method in which the electronic densities of small fragments determined by Kohn-Sham density functional theory (DFT) are embedded using stochastic DFT to form the exact density of the full system. The new method preserves the scaling and the simplicity of the stochastic DFT but cures the slow convergence that occurs when weakly coupled subsystems are treated. It overcomes the spurious charge fluctuations that impair the applications of the original stochastic DFT approach. We demonstrate the new approach on a fullerene dimer and on clusters of water molecules and show that the density of states and the totalmore » energy can be accurately described with a relatively small number of stochastic orbitals.« less
  • We present a study of the electronic excitations in insulating materials using an embedded- cluster method. The excited states of the embedded cluster are studied systematically using time-dependent density functional theory (TDDFT) and high-level equation-of-motion coupled cluster (EOMCC) methods. In particular, we have used EOMCC models with singles and doubles (EOMCCSD) and two approaches which account for the e®ect of triply excited con¯gurations in non-iterative and iterative fashions. We present calculations of the lowest surface excitations of the well-studied potassium bromide (KBr) system and compare our results with experiment. The bulk-surface exciton shift is also calculated at the TDDFT levelmore » and compared with experiment.« less
  • The properties of small neutral and positively charged sodium clusters and the fragmentation dynamics of Na{sup ++}{sub 4} are investigated using a simulation technique which combines classical molecular dynamics on the electronic Born--Oppenheimer ground-state potential surface with electronic structure calculations via the local spin-density functional method. Results for the optimal energies and structures of Na{sub {ital n}} and Na{sup +}{sub {ital n}} ({ital n}{le}4) are in quantitative agreement with previous studies and experimental data. Fission of Na{sup ++}{sub 4} on its ground state Born--Oppenheimer potential-energy surface, following sudden ionization of selected configurations of an Na{sup +}{sub 4} (or Na{sub 4})more » cluster, whose vibrational energy content corresponds to 300 K, is found to occur on a picosecond time scale. The preferred fission channel is found to be Na{sup +}{sub 3}+Na{sup +}, with an interfragment relative translational kinetic energy of {similar to}2 eV, and a vibrationally excited Na{sup +}{sub 3}. The dynamics of the fragmentation process is analyzed.« less
  • In this paper, four methods to calculate charge transfer integrals in the context of bridge-mediated electron transfer are tested. These methods are based on density functional theory (DFT). We consider two perturbative Green's function effective Hamiltonian methods (first, at the DFT level of theory, using localized molecular orbitals; second, applying a tight-binding DFT approach, using fragment orbitals) and two constrained DFT implementations with either plane-wave or local basis sets. To assess the performance of the methods for through-bond (TB)-dominated or through-space (TS)-dominated transfer, different sets of molecules are considered. For through-bond electron transfer (ET), several molecules that were originally synthesizedmore » by Paddon-Row and co-workers for the deduction of electronic coupling values from photoemission and electron transmission spectroscopies, are analyzed. The tested methodologies prove to be successful in reproducing experimental data, the exponential distance decay constant and the superbridge effects arising from interference among ET pathways. For through-space ET, dedicated p-stacked systems with heterocyclopentadiene molecules were created and analyzed on the basis of electronic coupling dependence on donor-acceptor distance, structure of the bridge, and ET barrier height. The inexpensive fragment-orbital density functional tight binding (FODFTB) method gives similar results to constrained density functional theory (CDFT) and both reproduce the expected exponential decay of the coupling with donor-acceptor distances and the number of bridging units. Finally, these four approaches appear to give reliable results for both TB and TS ET and present a good alternative to expensive ab initio methodologies for large systems involving long-range charge transfers.« less