Excited vibrational states of polyatomic molecules

The semiclassical self-consistent field approach

Mark A Ratner, R. B. Gerber

Research output: Contribution to journalArticle

150 Citations (Scopus)

Abstract

An outline is given of self-consistent field methods for treating the coupled vibrations of polyatomic systems and some applications to energy level structure and dissociation dynamics of molecules and clusters are described. The SCF approximation describes each mode as moving in an average field of all other modes; the mean fields for the single modes are determined by a self-consistency condition. The method is computationally simple, applicable to relatively large systems, and can be formulated for static or for time-dependent problems, in classical, semiclassical, or quantum representations. We discuss several aspects of static SCF, including vibrational energy level and eigenstate determination, with applications to spectroscopy of highly excited states, inversion methods for obtaining polyatomic potential surfaces, metastable states, and finally the validity range of SCF and its extensions. For time-dependent SCF, we discuss dissociation of van der Waals molecules both in the strong coupling (Ar3, RRKM-like) and weak coupling (I2Ne, Slater-like) regimes, and vibrational relaxation in polyatomic clusters (I2NeN). In each of these cases, SCF techniques are fairly accurate, and offer convenient physical interpretation. We believe that these advantages will result in an important place for these SCF methods in the theoretical discussion of vibrational energy states, flow, and dynamics.

Original languageEnglish
Pages (from-to)20-30
Number of pages11
JournalJournal of Physical Chemistry
Volume90
Issue number1
Publication statusPublished - 1986

Fingerprint

polyatomic molecules
vibrational states
Electron energy levels
self consistent fields
Molecules
Surface potential
Excited states
Spectroscopy
energy levels
dissociation
molecular relaxation
metastable state
molecules
eigenvectors
inversions
vibration
approximation
spectroscopy
excitation

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

Excited vibrational states of polyatomic molecules : The semiclassical self-consistent field approach. / Ratner, Mark A; Gerber, R. B.

In: Journal of Physical Chemistry, Vol. 90, No. 1, 1986, p. 20-30.

Research output: Contribution to journalArticle

@article{5e5ecc335c0c4b239ca39e7955a56f3d,
title = "Excited vibrational states of polyatomic molecules: The semiclassical self-consistent field approach",
abstract = "An outline is given of self-consistent field methods for treating the coupled vibrations of polyatomic systems and some applications to energy level structure and dissociation dynamics of molecules and clusters are described. The SCF approximation describes each mode as moving in an average field of all other modes; the mean fields for the single modes are determined by a self-consistency condition. The method is computationally simple, applicable to relatively large systems, and can be formulated for static or for time-dependent problems, in classical, semiclassical, or quantum representations. We discuss several aspects of static SCF, including vibrational energy level and eigenstate determination, with applications to spectroscopy of highly excited states, inversion methods for obtaining polyatomic potential surfaces, metastable states, and finally the validity range of SCF and its extensions. For time-dependent SCF, we discuss dissociation of van der Waals molecules both in the strong coupling (Ar3, RRKM-like) and weak coupling (I2Ne, Slater-like) regimes, and vibrational relaxation in polyatomic clusters (I2NeN). In each of these cases, SCF techniques are fairly accurate, and offer convenient physical interpretation. We believe that these advantages will result in an important place for these SCF methods in the theoretical discussion of vibrational energy states, flow, and dynamics.",
author = "Ratner, {Mark A} and Gerber, {R. B.}",
year = "1986",
language = "English",
volume = "90",
pages = "20--30",
journal = "Journal of Physical Chemistry",
issn = "0022-3654",
publisher = "American Chemical Society",
number = "1",

}

TY - JOUR

T1 - Excited vibrational states of polyatomic molecules

T2 - The semiclassical self-consistent field approach

AU - Ratner, Mark A

AU - Gerber, R. B.

PY - 1986

Y1 - 1986

N2 - An outline is given of self-consistent field methods for treating the coupled vibrations of polyatomic systems and some applications to energy level structure and dissociation dynamics of molecules and clusters are described. The SCF approximation describes each mode as moving in an average field of all other modes; the mean fields for the single modes are determined by a self-consistency condition. The method is computationally simple, applicable to relatively large systems, and can be formulated for static or for time-dependent problems, in classical, semiclassical, or quantum representations. We discuss several aspects of static SCF, including vibrational energy level and eigenstate determination, with applications to spectroscopy of highly excited states, inversion methods for obtaining polyatomic potential surfaces, metastable states, and finally the validity range of SCF and its extensions. For time-dependent SCF, we discuss dissociation of van der Waals molecules both in the strong coupling (Ar3, RRKM-like) and weak coupling (I2Ne, Slater-like) regimes, and vibrational relaxation in polyatomic clusters (I2NeN). In each of these cases, SCF techniques are fairly accurate, and offer convenient physical interpretation. We believe that these advantages will result in an important place for these SCF methods in the theoretical discussion of vibrational energy states, flow, and dynamics.

AB - An outline is given of self-consistent field methods for treating the coupled vibrations of polyatomic systems and some applications to energy level structure and dissociation dynamics of molecules and clusters are described. The SCF approximation describes each mode as moving in an average field of all other modes; the mean fields for the single modes are determined by a self-consistency condition. The method is computationally simple, applicable to relatively large systems, and can be formulated for static or for time-dependent problems, in classical, semiclassical, or quantum representations. We discuss several aspects of static SCF, including vibrational energy level and eigenstate determination, with applications to spectroscopy of highly excited states, inversion methods for obtaining polyatomic potential surfaces, metastable states, and finally the validity range of SCF and its extensions. For time-dependent SCF, we discuss dissociation of van der Waals molecules both in the strong coupling (Ar3, RRKM-like) and weak coupling (I2Ne, Slater-like) regimes, and vibrational relaxation in polyatomic clusters (I2NeN). In each of these cases, SCF techniques are fairly accurate, and offer convenient physical interpretation. We believe that these advantages will result in an important place for these SCF methods in the theoretical discussion of vibrational energy states, flow, and dynamics.

UR - http://www.scopus.com/inward/record.url?scp=33845375177&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33845375177&partnerID=8YFLogxK

M3 - Article

VL - 90

SP - 20

EP - 30

JO - Journal of Physical Chemistry

JF - Journal of Physical Chemistry

SN - 0022-3654

IS - 1

ER -