Structures and energetics of CO2-Ar-n clusters (n=1-21) based on a non-rigid potential model


Boeyuekata M. , Borges E., Belchior J. C. , Braga J. P.

CANADIAN JOURNAL OF CHEMISTRY, vol.85, no.1, pp.47-55, 2007 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 85 Issue: 1
  • Publication Date: 2007
  • Doi Number: 10.1139/v06-178
  • Title of Journal : CANADIAN JOURNAL OF CHEMISTRY
  • Page Numbers: pp.47-55
  • Keywords: argon, CO2, cluster, potential energy function, molecular dynamics, INFRARED-ABSORPTION SPECTROSCOPY, SHAPED VANDERWAALS COMPLEXES, GLOBAL GEOMETRY OPTIMIZATION, HIGH-RESOLUTION SPECTROSCOPY, LENNARD-JONES CLUSTERS, DER-WAALS COMPLEXES, QUANTUM MONTE-CARLO, TO-STATE LEVEL, ENERGY SURFACES, MOLECULAR-DYNAMICS

Abstract

Energetics and possible stable structures of CO2-Ar-n (n = 1-21) clusters are investigated by performing molecular-dynamics simulations. The pairwise-additive approximation is tested to construct the potential energy function for describing the non-rigid particle interactions in the system. A potential model by Pariseau et al. (Journal of Chemical Physics, Vol. 42, p. 2335, 1965) is used for the internal motion of the CO2 molecule and the Billing form potential (Chemical Physics, Vol. 185, p. 199, 1994) is used for all other pair interactions. The stable configurations are determined for the ground state of CO2-Ar-n clusters, and the growing pattern process of the clusters is determined via rearrangement collisions. Ar atoms tend to surround the CO2 molecule, and the clusters prefer to form three-dimensional compact structures. Obtained structures and energetics are in quantitative agreement with previous results (Journal of Chemical Physics, Vol. 109, p. 1343, 1998) that have used split-repulsion and ab initio potentials in which the molecule was treated as rigid.