Experimental and theoretical studies of adsorption of CH3 on α-Fe2O3 (0 0 0 1) surfaces

Experimental and theoretical studies of adsorption of methyl on hematite (0 0 0 1) were carried out using a novel source of the methyl radicals, TPD, AES, QMS, LEED and density functional theory. The crystal surface was not very well characterized experimentally, due to the possible co-existence of several phases and tendency to form magnetite overlayers. Thus observed weak methyl adsorption could be tentatively assigned to defect sites. DFT pseudopotential supercell band structure calculations on clean and adsorbed idealized surfaces predict that the partially oxidized “ferryl structure” has largest adsorption energy, and that regular sites could also adsorb methyl radicals. Embedded-cluster models were used to extract local bonding information and details of electronic structure.