THE INTERACTION OF ATOMIC-HYDROGEN WITH CU(110)

The interaction of atomic hydrogen with Cu(110) has been investigated by thermal desorption spectroscopy and by surface state spectroscopy u sing ultraviolet photoemission and inverse photoemission. Atomic H fir st forms a chemisorption layer, which saturates at a coverage of appro ximately 0.5 monolayers. At low temperature further exposure leads to a thermal desorption peak which was not observed hitherto. We attribut e it to H absorption into subsurface sites. The surface state shifts c aused by the adsorption of hydrogen on Cu(110) show striking parallels to those observed upon hydrogen adsorption on Ni(110). The (1 x 2) re construction of the H/Cu(110) surface gives rise to a surface state sh ift which is characteristic for a missing or added row phase. The inte nsity variation of the surface states during the formation of the (1 x 2) phase indicates the formation of large islands. An occupied surfac e state on H/Cu(110) contributes to the stabilization of these islands .