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Title: Molecular dynamics computer simulation of permeation in solids

In this work the authors simulate permeation of gases and cations in solid models using molecular mechanics and a dual control volume grand canonical molecular dynamics technique. The molecular sieving nature of microporous zeolites are discussed and compared with that for amorphous silica made by sol-gel methods. One mesoporous and one microporous membrane model are tested with Lennard-Jones gases corresponding to He, H{sub 2}, Ar and CH{sub 4}. The mesoporous membrane model clearly follows a Knudsen diffusion mechanism, while the microporous model having a hard-sphere cutoff pore diameter of {approximately}3.4 {angstrom} demonstrates molecular sieving of the methane ({sigma} = 3.8 {angstrom}) but anomalous behavior for Ar ({sigma} = 3.4 {angstrom}). Preliminary results of Ca{sup +} diffusion in calcite and He/H{sub 2} diffusion in polyisobutylene are also presented.
Authors:
; ; ;  [1]
  1. Sandia National Labs., Albuquerque, NM (United States)
Publication Date:
OSTI Identifier:
332758
Report Number(s):
SAND--98-1591; CONF-9709141--PROC.
ON: DE99000778; TRN: IM9916%%60
Resource Type:
Conference
Resource Relation:
Conference: 5. joint Russian-American computational mathematics conference, Albuquerque, NM (United States), 2-5 Sep 1997; Other Information: PBD: [1997]; Related Information: Is Part Of Proceedings of the 5. joint Russian-American computational mathematics conference; PB: 312 p.
Research Org:
Sandia National Labs., Albuquerque, NM (United States)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 99 MATHEMATICS, COMPUTERS, INFORMATION SCIENCE, MANAGEMENT, LAW, MISCELLANEOUS; PERMEABILITY; DIFFUSION; MOLECULAR DYNAMICS METHOD; ZEOLITES; SILICA; HELIUM; HYDROGEN; ARGON; METHANE; MATHEMATICAL MODELS; ATOM TRANSPORT; CALCIUM; CALCITE; ORGANIC POLYMERS