title: First-principles calculations of the adsorption of nitromethane and 1,1-diamino-2,2-dinitroethylene (FOX-7) molecules on the alpha-Al2O3(0001) surface.
abstract: First-principles calculations based on density functional theory (DFT) and the generalized gradient approximation (GGA) have been used to study the adsorption of nitromethane (NM) and 1,1-diamino-2,2-dinitroethylene (FOX-7) molecules on the basal plane of an alpha-Al(2)O(3) crystal. The calculations employ a (2 x 2) supercell slab model and 3D periodic boundary conditions. On the basis of these calculations, we have determined that both NM and FOX-7 molecules can adsorb nondissociatively on the surface with the most stable adsorption configurations parallel to the surface. The binding energies are in the range 25.3-26.0 kcal/mol for NM and 35.6-48.3 kcal/mol for FOX-7 depending on the relative molecular orientation and the surface sites. The minimum energy pathways for NM dissociation have been determined, and a low-energy pathway leading to H-atom elimination with formation of adsorbed CH(2)NO(2) and hydroxyl species has been identified. Additional calculations have focused on adsorption properties of aci-nitromethane tautomers and on description of the energetic pathways connecting adsorbed nitromethane molecule with these tautomers.
authors.affiliation: National Energy Technology Laboratory, U.S. Department of Energy, Pittsburgh, PA 15236, USA.
authors.forename: Dan C
authors.initials: DC
authors.lastname: Sorescu
authors.forename: Jerry A
authors.initials: JA
authors.lastname: Boatz
authors.forename: Donald L
authors.initials: DL
authors.lastname: Thompson
mesh_terms: D000327:Adsorption; D000537:Aluminum Oxide / Q000737:chemistry*; D005030:Ethylenes / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D008956:Models, Chemical; D009574:Nitro Compounds / Q000737:chemistry*; D009595:Nitroparaffins / Q000737:chemistry*; D055672:Static Electricity; D013499:Surface Properties
chemical_list: C520681:1,1-diamino-2,2-dinitroethylene; D005030:Ethylenes; D009574:Nitro Compounds; D009595:Nitroparaffins; D000537:Aluminum Oxide; D008697:Methane; C008640:nitromethane