Effect of Triplet Correlations on the Adsorption of a Dense Fluid Onto a Crystalline Surface
Abstract
The adsorption of a fluid of hard spheres of diameter a onto a planar surface containing a triangular lattice of adsorption sites, spacing sigma, was studied using a model which is equivalent to a lattice gas with n-body interactions that are related to the n-body correlation functions of the fluid. The present paper extends our previous work, which included only pairwise interactions, to also include triplet interactions. We discovered a simple but accurate analytical approximation to the triplet correlation function for three spheres in mutual contact, which, when combined with a Muller-Hartmann and Zittarz approximation of the critical point in the equivalent lattice gas, yields the estimate p sub c sigma 13=O.8409 of the fluid density at the critical point of the condensation transition which occurs at the fluid-crystal interface. This estimate, which includes the effects of both pair and triplet correlations in the fluid, is significantly higher than the value p sub c sigma 13=O.6678 obtained if only the effects of pair correlation are included in the calculation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 15, 1993
- Accession Number
- ADA260306
Entities
People
- Dale A. Huckaby
- Lesser Blum
Organizations
- University of Puerto Rico