A study of the energetics of the Cl[sub 2]/MgO(001) interface using correlation corrected periodic Hartree--Fock theory

Journal Article · Thu Apr 15 04:00:00 EDT 1993 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.464835· OSTI ID:6697066

McCarthy, M I; Hess, A C ^[1]; Harrison, N M; Saunders, V R ^[2]

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1. Molecular Sciences Research Center, Pacific Northwest Laboratory, Richland, WA 99352 (United States)
2. SERC Daresbury Laboratory, Daresbury, Warrington WA4 4AD (United Kingdom)

The energetics of the Cl[sub 2]/MgO(001) interface were investigated using the [ital ab] [ital initio] periodic Hartree--Fock (PHF) method and local density functional correlation corrections to PHF theory, as implemented in the program CRYSTAL92. Estimates of the correlation corrected PHF energies are made by post-SCF evaluations of three gradient corrected functionals. The correlation energy is calculated from the fully converged ground state PHF charge density and added to the PHF total energy. This is the first study of interfacial energetics using the correlation corrected PHF theory. PHF and correlation corrected molecule/surface binding energies are reported for seven orientations of the adsorbate with respect to the surface plane. Three of the configurations align the intramolecular axes along the surface normal and the remaining geometries arrange the molecules heat-to-tail, parallel to the surface plane. The most favorable interaction occurs when chlorine approaches a surface oxygen along the normal direction. This site preference is consistent with a classical electrostatic description of the physisorption process. The binding energy increases with decreasing surface coverage. At the most dilute coverage studied (1:8) the PHF binding energy was 4.1 kcal/mol and the correlation corrected binding energies ranged from 9.2 to 10.3 kcal/mol. All three functionals tended to increase the molecule/surface attractions, shorten the molecule/surface equilibrium distance, increase the curvature of the molecule/surface potential energy surface near equilibrium, and reduce the molecule/molecule repulsions.

• DOE Contract Number: AC06-76RL01830
• OSTI ID: 6697066
• Journal Information: Journal of Chemical Physics; (United States), Journal Name: Journal of Chemical Physics; (United States) Vol. 98:8; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

664100 -- Theory of Electronic Structure of Atoms & Molecules-- (1992-)
665000* -- Physics of Condensed Matter-- (1992-)
74 ATOMIC AND MOLECULAR PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
BINDING ENERGY
CALCULATION METHODS
CHALCOGENIDES
CHLORINE
CORRECTIONS
ELEMENTS
ENERGY
HALOGENS
HARTREE-FOCK METHOD
INTERFACES
MAGNESIUM COMPOUNDS
MAGNESIUM OXIDES
NONMETALS
OXIDES
OXYGEN COMPOUNDS