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1994

Interactions

Articles 1 - 2 of 2

Full-Text Articles in Physics

Asymmetric Adsorbate And Substrate Interactions In Physisorbed Systems: N2 On Graphite And Dipolar Molecules On Ionic Substrates, Teresa Ellen Burns Aug 1994

Asymmetric Adsorbate And Substrate Interactions In Physisorbed Systems: N2 On Graphite And Dipolar Molecules On Ionic Substrates, Teresa Ellen Burns

All Graduate Theses and Dissertations

Asymmetries in physisorbed systems give rise to interesting phases and phase transitions in two-dimensional (2D) monolayer and multilayer systems. The effects of asymmetric adsorbate and substrate interactions in monolayers of dipolar molecules on ionic substrates and N2 on graphite are studied.

In the case of dipolar molecules on ionic substrates, 2D dielectric phase transitions using a modified Blume-Emery-Griffiths (BEG) model are determined theoretically. A dipole adsorbed vertically above a metal ion lattice site, and pointing up (down), is assigned a spin s=+1 (s=-1). An empty lattice site is assigned a spin S=0. Analytic solutions for both ...


A Monte Carlo Simulation Of Coulomb Collisions And Wave-Particle Interactions In Space Plasma At High Lattitudes, Imad Ahmad Barghouthi May 1994

A Monte Carlo Simulation Of Coulomb Collisions And Wave-Particle Interactions In Space Plasma At High Lattitudes, Imad Ahmad Barghouthi

All Graduate Theses and Dissertations

Four studies were considered to simulate the ion behavior in the auroral region and the polar wind.

In study I, a Monte Carlo simulation was used to investigate the behavior of O+ ions that are E x B-drifting through a background of neutral O, with the effect of O+(Coulomb) self-collisions included. Wide ranges of the ion-to-neutral density ratio ni|nn and electrostatic field E were considered in order to investigate the change of ion behavior with respect to the solar cycle and altitude. For low altitudes and/or solar minimum (ni|nn≤10-5), the ...