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Title: A perturbative formalism for electronic transitions through conical intersections in a fully quadratic vibronic model

Abstract

We consider a fully quadratic vibronic model Hamiltonian for studying photoinduced electronic transitions through conical intersections. Using a second order perturbative approximation for diabatic couplings, we derive an analytical expression for the time evolution of electronic populations at a given temperature. This formalism extends upon a previously developed perturbative technique for a linear vibronic coupling Hamiltonian. The advantage of the quadratic model Hamiltonian is that it allows one to use separate quadratic representations for potential energy surfaces of different electronic states and a more flexible representation of interstate couplings. We explore features introduced by the quadratic Hamiltonian in a series of 2D models, and then apply our formalism to the 2,6-bis(methylene) adamantyl cation and its dimethyl derivative. The Hamiltonian parameters for the molecular systems have been obtained from electronic structure calculations followed by a diabatization procedure. The evolution of electronic populations in the molecular systems using the perturbative formalism shows a good agreement with that from variational quantum dynamics.

Authors:
; ;  [1];  [2]
  1. Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario M1C 1A4 (Canada)
  2. (Canada)
Publication Date:
OSTI Identifier:
22419876
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 3; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS; APPROXIMATIONS; CATIONS; COUPLINGS; ELECTRONIC STRUCTURE; HAMILTONIANS; POTENTIAL ENERGY; SURFACES

Citation Formats

Endicott, Julia S., Joubert-Doriol, Loïc, Izmaylov, Artur F., E-mail: artur.izmaylov@utoronto.ca, and Chemical Physics Theory Group, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6. A perturbative formalism for electronic transitions through conical intersections in a fully quadratic vibronic model. United States: N. p., 2014. Web. doi:10.1063/1.4887258.
Endicott, Julia S., Joubert-Doriol, Loïc, Izmaylov, Artur F., E-mail: artur.izmaylov@utoronto.ca, & Chemical Physics Theory Group, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6. A perturbative formalism for electronic transitions through conical intersections in a fully quadratic vibronic model. United States. doi:10.1063/1.4887258.
Endicott, Julia S., Joubert-Doriol, Loïc, Izmaylov, Artur F., E-mail: artur.izmaylov@utoronto.ca, and Chemical Physics Theory Group, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6. Mon . "A perturbative formalism for electronic transitions through conical intersections in a fully quadratic vibronic model". United States. doi:10.1063/1.4887258.
@article{osti_22419876,
title = {A perturbative formalism for electronic transitions through conical intersections in a fully quadratic vibronic model},
author = {Endicott, Julia S. and Joubert-Doriol, Loïc and Izmaylov, Artur F., E-mail: artur.izmaylov@utoronto.ca and Chemical Physics Theory Group, Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6},
abstractNote = {We consider a fully quadratic vibronic model Hamiltonian for studying photoinduced electronic transitions through conical intersections. Using a second order perturbative approximation for diabatic couplings, we derive an analytical expression for the time evolution of electronic populations at a given temperature. This formalism extends upon a previously developed perturbative technique for a linear vibronic coupling Hamiltonian. The advantage of the quadratic model Hamiltonian is that it allows one to use separate quadratic representations for potential energy surfaces of different electronic states and a more flexible representation of interstate couplings. We explore features introduced by the quadratic Hamiltonian in a series of 2D models, and then apply our formalism to the 2,6-bis(methylene) adamantyl cation and its dimethyl derivative. The Hamiltonian parameters for the molecular systems have been obtained from electronic structure calculations followed by a diabatization procedure. The evolution of electronic populations in the molecular systems using the perturbative formalism shows a good agreement with that from variational quantum dynamics.},
doi = {10.1063/1.4887258},
journal = {Journal of Chemical Physics},
number = 3,
volume = 141,
place = {United States},
year = {Mon Jul 21 00:00:00 EDT 2014},
month = {Mon Jul 21 00:00:00 EDT 2014}
}