Copper interface induced relaxation of ${\mathrm{TiO}}_2\mathrm{}\left(110\right)-1\mathrm{}\times 1$

Surface x-ray diffraction has been used to examine the effect of a Cu overlayer on the bulk structural relaxations of ${\mathrm{TiO}}_2\mathrm{}\left(110\right)1\times 1).$ The Ti atoms at this buried interface are at close to their bulk-terminated positions, representing a derelaxation from the clean surface positions by up to about 0.2 Å. In contrast, O atom vertical and lateral displacements are enhanced, with values of up to 0.4±0.1 Å and 0.6±0.1 Å, respectively. This enhanced relaxation is consistent with Cu-O bonding.