Collision kernel and interatomic potential

Journal Article · Thu May 01 04:00:00 EDT 1986 · Phys. Rev. A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.33.3067· OSTI ID:5874160

Ho, T; Chu, S

We present a detailed study of the influence of the form and strength of the interatomic potential on the one-dimensional elastic collision kernel W(v/sub z//sup prime/,v/sub z/), a quantity of interest in the study of the effects of velocity-changing collisions on laser spectroscopic line shapes. We find that the absolute magnitudes of collision kernels are very sensitive while normalized collision kernels are moderately sensitive to the potential form used. This indicates the importance of employing realistic interatomic potentials and reliable differential cross sections in the accurate determination of collision kernels. For the case of the Lennard-Jones (12,6) potential, we found a universal semiclassical Lennard-Jones (SCLJ) analytical model function, which is the combination of a semiclassical expression for small to medium scattering angles and a classical expression for large scattering angles, capable of providing correct average quantum-mechanical behaviors of differential cross sections for all scattering angles. This greatly facilitates the (often time-consuming) numerical evaluation of the collision kernel integrals and exhibits the correct collision kernel line profiles.

• Research Organization: Department of Chemistry, University of Kansas, Lawrence, Kansas 66045
• OSTI ID: 5874160
• Journal Information: Phys. Rev. A; (United States), Journal Name: Phys. Rev. A; (United States) Vol. 33:5; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ALKALI METALS
ARGON
ATOM COLLISIONS
ATOM-ATOM COLLISIONS
COLLISIONS
CROSS SECTIONS
DIFFERENTIAL CROSS SECTIONS
ELEMENTS
EQUATIONS
FLUIDS
GASES
INTEGRAL EQUATIONS
INTERATOMIC FORCES
KERNELS
LASER SPECTROSCOPY
LINE WIDTHS
MATHEMATICAL MODELS
METALS
NONMETALS
POTENTIALS
RARE GASES
SODIUM
SPECTROSCOPY
VELOCITY