Corrections to the Born-Oppenheimer approximation by means of perturbation theory

Journal Article · Sat Oct 01 00:00:00 EDT 1994 · Physical Review A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.50.2953· OSTI ID:7203718

Fernandez, F M ^[1]

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1. Departamento de Quimica Fisica, Universidad de Extremadura, 06071 Badajoz (Spain)

We develop an efficient method for the calculation of corrections to the Born-Oppenheimer approximation by means of perturbation theory. The perturbation terms through sixth order in the small parameter [kappa]=([ital m]/[ital M])[sup 1/4], where [ital m] and [ital M] are, respectively, electronic and nuclear masses, allow the construction of an effective vibrational Hamiltonian that takes into account adiabatic and nonadiabatic effects. The latter is negative and linearly dependent on the vibrational quantum numbers. We illustrate the application of the main equations and verify the general results by means of an exactly solvable model of two coupled harmonic oscillators.

• OSTI ID: 7203718
• Journal Information: Physical Review A; (United States), Vol. 50:4; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
HYDROGEN IONS 2 PLUS
BORN-OPPENHEIMER APPROXIMATION
CALCULATION METHODS
CORRECTIONS
ELECTRONIC STRUCTURE
ENERGY LEVELS
MOLECULAR IONS
MOLECULES
PERTURBATION THEORY
CATIONS
CHARGED PARTICLES
HYDROGEN IONS
IONS
664100* - Theory of Electronic Structure of Atoms & Molecules- (1992-)