Abstract
We use a classical transition state theory (TST) to calculate the diffusion constant for noble gas atoms through silica sodalite. Due to the restrictive geometry of the transition state, diffusion of Ne and Ar is energy-activated at room temperature, but the diffusion of He is limited by entropy. The small mass of He suggests that a quantum TST must be employed. Path integral Monte Carlo is used to perform the relevant sampling, and quantum and classical diffusivities are compared. Comparison reveals a competition between tunneling and diffraction of the quantum mechanical He atom. A pairwise centroid pseudopotential is developed for the guest−host atom pair, and the effective potential energy and TST rate are compared with that of direct quantum TST.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
