Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Density functional theory calculations of adsorption of water at calcium oxide and calcium fluoride surfaces
Autore:
de Leeuw, NH; Purton, JA; Parker, SC; Watson, GW; Kresse, G;
Indirizzi:
Univ Reading, Dept Chem, Reading RG6 6AH, Berks, England Univ Reading Reading Berks England RG6 6AH eading RG6 6AH, Berks, England Daresbury Lab, Warrington WA4 4AD, Cheshire, England Daresbury Lab Warrington Cheshire England WA4 4AD 4AD, Cheshire, England Univ Bath, Sch Chem, Bath BA2 7AY, Avon, England Univ Bath Bath Avon England BA2 7AY Sch Chem, Bath BA2 7AY, Avon, England Univ Dublin Trinity Coll, Dept Chem, Dublin 2, Ireland Univ Dublin TrinityColl Dublin Ireland 2 , Dept Chem, Dublin 2, Ireland Univ Vienna, Inst Mat Phys, A-1090 Vienna, Austria Univ Vienna Vienna Austria A-1090 Inst Mat Phys, A-1090 Vienna, Austria
Titolo Testata:
SURFACE SCIENCE
fascicolo: 1-3, volume: 452, anno: 2000,
pagine: 9 - 19
SICI:
0039-6028(20000501)452:1-3<9:DFTCOA>2.0.ZU;2-J
Fonte:
ISI
Lingua:
ENG
Soggetto:
TOTAL-ENERGY CALCULATIONS; WAVE BASIS-SET; ATOMISTIC SIMULATION; MAGNESIUM-OXIDE; DISSOCIATIVE ADSORPTION; MOLECULAR-DYNAMICS; FORCE MICROSCOPY; MGO(001) SURFACE; FIRST-PRINCIPLES; HARTREE-FOCK;
Keywords:
alkaline earth metals; density functional calculations; surface energy; surface structure, morphology, roughness, and; topography; water;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
49
Recensione:
Indirizzi per estratti:
Indirizzo: de Leeuw, NH Univ Reading, Dept Chem, Reading RG6 6AH, Berks, England UnivReading Reading Berks England RG6 6AH H, Berks, England
Citazione:
N.H. de Leeuw et al., "Density functional theory calculations of adsorption of water at calcium oxide and calcium fluoride surfaces", SURF SCI, 452(1-3), 2000, pp. 9-19

Abstract

Electronic structure calculations using the density functional theory (DFT) within the generalized-gradient approximation and ultra-soft pseudopotentials have been used to investigate the adsorption of water on the main cleavage planes of CaO and CaF2. The calculated structural parameters are foundto be in good agreement with experiment. The unhydrated surfaces show negligible ionic relaxation from bulk termination due to the minimal distortionof the electron density in the surface layer. Electron density plots show both crystals to be strongly ionic. We found on both mineral surfaces that associative adsorption of water is energetically preferred. Water moleculeswhich were initially dissociatively adsorbed, recombined to form associatively adsorbed species. The water molecules are adsorbed by their oxygen ionto surface calcium ions, but electron density plots show strong interactions between surface anions and hydrogen atoms. The calculated hydration energies of approximately 70 kJ mol(-1) on the CaO {100} surface and 41-53 kJ mol(-1) on the CaF2 {111} surface indicate physisorption on both surfaces. (C) 2000 Elsevier Science B.V. All rights reserved.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 01/12/20 alle ore 07:36:39