Multilayer 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 multilayer Lanczos method, for computing vibrational energies and dipole transition intensities of polyatomic molecules without any dynamics approximation. The multilayer Lanczos method is developed by using a few advanced techniques including the guided spectral transform Lanczos method, multilayer Lanczos iteration approach, recursive residue generation method, and dipolewavefunction 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 problemindependent. 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 loworder 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:
 Department of Chemistry, Brookhaven National Laboratory, Upton, New York 119735000 (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, HuaGen, Email: hgy@bnl.gov. Multilayer 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, HuaGen, Email: hgy@bnl.gov. Multilayer Lanczos iteration approach to calculations of vibrational energies and dipole transition intensities for polyatomic molecules. United States. doi:10.1063/1.4906492.
Yu, HuaGen, Email: hgy@bnl.gov. 2015.
"Multilayer 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 = {Multilayer Lanczos iteration approach to calculations of vibrational energies and dipole transition intensities for polyatomic molecules},
author = {Yu, HuaGen, Email: hgy@bnl.gov},
abstractNote = {We report a rigorous full dimensional quantum dynamics algorithm, the multilayer Lanczos method, for computing vibrational energies and dipole transition intensities of polyatomic molecules without any dynamics approximation. The multilayer Lanczos method is developed by using a few advanced techniques including the guided spectral transform Lanczos method, multilayer Lanczos iteration approach, recursive residue generation method, and dipolewavefunction 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 problemindependent. 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 loworder 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 = 2015,
month = 1
}

We report a rigorous full dimensional quantum dynamics algorithm, the multilayer Lanczos method, for computing vibrational energies and dipole transition intensities of polyatomic molecules without any dynamics approximation. The multilayer Lanczos method is developed by using a few advanced techniques including the guided spectral transform Lanczos method, multilayer Lanczos iteration approach, recursive residue generation method, and dipolewavefunction 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 problemindependent. An applicationmore »Cited by 5

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