Effect of three-body forces on the statics and dynamics of SF6–(Rg)n and (Rg)13 clusters
- 1 April 1993
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 98 (7), 5668-5678
- https://doi.org/10.1063/1.464882
Abstract
Molecular dynamics and Monte Carlo simulations are used to examine the effect on the structural properties of heterogeneous SF6–(Ar)n and SF6–(Kr)n clusters, and on the melting behavior of heterogeneous SF6–(Ar)n and homogeneous (Ar)13 and (Kr)13 clusters, of including the three‐body Axilrod–Teller–Muto triple–dipole dispersion energies in the total potential energy surface governing the dynamics of the system. The behavior of these systems is governed by potentials constructed from the best available two‐body interactions, and from accurate constrained dipole oscillator strength values for the triple–dipole dispersion energy coefficients reported here for the first time. The structural studies show that (virtually) all isomers are destablized by inclusion of the three‐body terms, with the ‘‘stacked’’ or ‘‘nonwetting’’ structures being destablized relatively more than isomeric ‘‘monolayer’’ or ‘‘wetting’’ structures. However, the qualitative trends in relative stability are unchanged; in particular, the preference for the SF6 to be fully solvated in larger clusters formed with Ar, but to lie on the surface of larger clusters formed with Kr, remains unchanged. In contrast, the melting temperatures of the stacked and monolayer isomers of the heterogeneous SF6–(Ar)12 cluster undergo substantial change on inclusion of the three‐body terms, the former dropping from ca. 30 to 22 K and the latter from 10 to 6 K. The melting temperatures of the homogeneous (Ar)13 and (Kr)13 icosahedral isomers also decreased on inclusion of the three‐body interactions, and the resulting values are quite different than those obtained using the commonly accepted ‘‘effective’’ two‐body LJ(12,6) pair potentials for these systems.Keywords
This publication has 42 references indexed in Scilit:
- Infrared signatures for isomerization and melting in inhomogeneous van der Waals clustersThe Journal of Chemical Physics, 1991
- ACCURATE TRANSPORT PROPERTIES AND SECOND VIRIAL COEFFICIENTS FOR KRYPTON BASED ON A STATE-OF-THE-ART INTERATOMIC POTENTIALChemical Engineering Communications, 1989
- Melting and freezing in isothermal Ar13 clustersThe Journal of Chemical Physics, 1987
- High pressure equation of state for solid xenon from interatomic potentialsMolecular Physics, 1987
- The argon and krypton interatomic potentials revisitedMolecular Physics, 1986
- Many-body interactions in rare gasesMolecular Physics, 1986
- Multiproperty empirical anisotropic intermolecular potentials for ArSF6 and KrSF6The Journal of Chemical Physics, 1982
- Multiproperty empirical interatomic potentials for ArXe and KrXeThe Journal of Chemical Physics, 1982
- On the character of the melting transition in small atomic aggregatesThe Journal of Chemical Physics, 1977
- A new Monte Carlo method for calculating surface tensionThe Journal of Chemical Physics, 1976