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Title: Multi-layer Lanczos iteration approach to calculations of vibrational energies and dipole transition intensities for polyatomic molecules

Abstract

We report a rigorous full dimensional quantum dynamics algorithm, the multi-layer Lanczos method, for computing vibrational energies and dipole transition intensities of polyatomic molecules without any dynamics approximation. The multi-layer Lanczos method is developed by using a few advanced techniques including the guided spectral transform Lanczos method, multi-layer Lanczos iteration approach, recursive residue generation method, and dipole-wavefunction contraction. The quantum molecular Hamiltonian at the total angular momentum J = 0 is represented in a set of orthogonal polyspherical coordinates so that the large amplitude motions of vibrations are naturally described. In particular, the algorithm is general and problem-independent. An application is illustrated by calculating the infrared vibrational dipole transition spectrum of CH{sub 4} based on the ab initio T8 potential energy surface of Schwenke and Partridge [Spectrochimica Acta, Part A 57, 887 (2001)] and the low-order truncated ab initio dipole moment surfaces of Yurchenko et al. [J. Mol. Spectrosc. 291, 69 (2013)]. A comparison with experiments is made. The algorithm is also applicable for Raman polarizability active spectra.

Authors:
 [1]
  1. Department of Chemistry, Brookhaven National Laboratory, Upton, New York 11973-5000 (United States)
Publication Date:
OSTI Identifier:
22416034
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 4; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ALGORITHMS; ANGULAR MOMENTUM; COMPARATIVE EVALUATIONS; DIPOLE MOMENTS; DIPOLES; HAMILTONIANS; INFRARED SPECTRA; LAYERS; METHANE; MOLECULES; POLARIZABILITY; POTENTIAL ENERGY; RESIDUES; SURFACES; WAVE FUNCTIONS

Citation Formats

Yu, Hua-Gen, E-mail: hgy@bnl.gov. Multi-layer Lanczos iteration approach to calculations of vibrational energies and dipole transition intensities for polyatomic molecules. United States: N. p., 2015. Web. doi:10.1063/1.4906492.
Yu, Hua-Gen, E-mail: hgy@bnl.gov. Multi-layer Lanczos iteration approach to calculations of vibrational energies and dipole transition intensities for polyatomic molecules. United States. doi:10.1063/1.4906492.
Yu, Hua-Gen, E-mail: hgy@bnl.gov. Wed . "Multi-layer Lanczos iteration approach to calculations of vibrational energies and dipole transition intensities for polyatomic molecules". United States. doi:10.1063/1.4906492.
@article{osti_22416034,
title = {Multi-layer Lanczos iteration approach to calculations of vibrational energies and dipole transition intensities for polyatomic molecules},
author = {Yu, Hua-Gen, E-mail: hgy@bnl.gov},
abstractNote = {We report a rigorous full dimensional quantum dynamics algorithm, the multi-layer Lanczos method, for computing vibrational energies and dipole transition intensities of polyatomic molecules without any dynamics approximation. The multi-layer Lanczos method is developed by using a few advanced techniques including the guided spectral transform Lanczos method, multi-layer Lanczos iteration approach, recursive residue generation method, and dipole-wavefunction contraction. The quantum molecular Hamiltonian at the total angular momentum J = 0 is represented in a set of orthogonal polyspherical coordinates so that the large amplitude motions of vibrations are naturally described. In particular, the algorithm is general and problem-independent. An application is illustrated by calculating the infrared vibrational dipole transition spectrum of CH{sub 4} based on the ab initio T8 potential energy surface of Schwenke and Partridge [Spectrochimica Acta, Part A 57, 887 (2001)] and the low-order truncated ab initio dipole moment surfaces of Yurchenko et al. [J. Mol. Spectrosc. 291, 69 (2013)]. A comparison with experiments is made. The algorithm is also applicable for Raman polarizability active spectra.},
doi = {10.1063/1.4906492},
journal = {Journal of Chemical Physics},
number = 4,
volume = 142,
place = {United States},
year = {Wed Jan 28 00:00:00 EST 2015},
month = {Wed Jan 28 00:00:00 EST 2015}
}