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Title: Density Functional Investigation of the Adsorption of a Methane Monolayer on an Mg(100) Surface

Abstract

The adsorption of a monolayer of methane upon the (100) surface of MgO was studied using a first-principles-based density functional approach employing a plane-wave basis set and periodic boundary conditions. Adsorption at both magnesium and oxygen sites was investigated, as were methane orientations where one, two, or three hydrogen atoms point toward the surface plane. In addition, the effect of one methane molecule on its neighbors was investigated by considering arrangements where translational symmetry across the surface was accompanied by appropriate rotations of the methane molecule. The minimum-energy configuration has the methane molecules located directly above a surface magnesium atom, the principal axis of the C2v molecule is normal to the surface plane, and pairs of hydrogen atoms are oriented along the lattice lines that include adjacent (surface) oxygen atoms. Furthermore, neighboring methane molecules are rotated by 90 degrees to reduce the H-H steric interactions. This arrangement has direct ramifications for the stability of other proposed, similar arrangements.

Authors:
 [1];  [1];  [1];  [1]
  1. ORNL
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Center for Computational Sciences
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
931437
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B; Journal Volume: 73; Journal Issue: 6
Country of Publication:
United States
Language:
English
Subject:
03 NATURAL GAS; 08 HYDROGEN; ADSORPTION; ATOMS; BOUNDARY CONDITIONS; CONFIGURATION; FUNCTIONALS; HYDROGEN; MAGNESIUM; METHANE; OXYGEN; STABILITY; SYMMETRY

Citation Formats

Sumpter, Bobby G, Shelton Jr, William Allison, Larese, John Z, and Drummond, Michael L. Density Functional Investigation of the Adsorption of a Methane Monolayer on an Mg(100) Surface. United States: N. p., 2006. Web.
Sumpter, Bobby G, Shelton Jr, William Allison, Larese, John Z, & Drummond, Michael L. Density Functional Investigation of the Adsorption of a Methane Monolayer on an Mg(100) Surface. United States.
Sumpter, Bobby G, Shelton Jr, William Allison, Larese, John Z, and Drummond, Michael L. Sun . "Density Functional Investigation of the Adsorption of a Methane Monolayer on an Mg(100) Surface". United States. doi:.
@article{osti_931437,
title = {Density Functional Investigation of the Adsorption of a Methane Monolayer on an Mg(100) Surface},
author = {Sumpter, Bobby G and Shelton Jr, William Allison and Larese, John Z and Drummond, Michael L},
abstractNote = {The adsorption of a monolayer of methane upon the (100) surface of MgO was studied using a first-principles-based density functional approach employing a plane-wave basis set and periodic boundary conditions. Adsorption at both magnesium and oxygen sites was investigated, as were methane orientations where one, two, or three hydrogen atoms point toward the surface plane. In addition, the effect of one methane molecule on its neighbors was investigated by considering arrangements where translational symmetry across the surface was accompanied by appropriate rotations of the methane molecule. The minimum-energy configuration has the methane molecules located directly above a surface magnesium atom, the principal axis of the C2v molecule is normal to the surface plane, and pairs of hydrogen atoms are oriented along the lattice lines that include adjacent (surface) oxygen atoms. Furthermore, neighboring methane molecules are rotated by 90 degrees to reduce the H-H steric interactions. This arrangement has direct ramifications for the stability of other proposed, similar arrangements.},
doi = {},
journal = {Physical Review B},
number = 6,
volume = 73,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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