Theoretical study of the migration behaviour of Y-C atoms on diamond (001) surface

To develop a new type of diamond composite film, the adsorption energies and minimum migration energies of a single yttrium atom on a diamond (001) surface were calculated with the first principle method based on density functional theory (DFT). Moreover, the total energies of some 1C1Y and 2C1Y configurations and their evolution energies were calculated to study the effect of yttrium additions. The investigation results showed that (1) the migration activation energies of a single yttrium atom along a dimer row and a dimer chain were 0.3505 eV and 1.0128 eV, respectively, indicating that migration of an yttrium atom on a diamond (001) surface is relatively easy; and (2) the migration activation energies of the carbon atoms in configurations of 2C1Y three atoms were obviously reduced, manifesting that the yttrium addition has promotion effects on migration of the carbon atoms on a clean diamond (001) surface. (C) 2015 Elsevier B.V. All rights reserved.