Novel properties of surfaces with heteronanostructures are of considerable interest in recent years. Although glycine can only be physisorbed on pure sil ver surfaces, our recent results show that monolayersilver islands deposited o n copper surfaces, with the help from the nearby nude copper surface areas, have the ability of chemisorption of glycine. In the present study we find that, on the other way round, copper islands deposited on the Ag(111) surface can also ma ke glycine being chemisorbed on the nude silver areas, although in the latter ca se the surface of a silver bulk is involved. This result demonstrates that it is the nanocoexistance of Cu and Ag on the surface, rather than any specific str ucture of the coexistance, that gives rise to the novel chemical property of the silver surfaces. Furthermore, we also find that all deposited copper islands will gradually be covered by a monolayer of Ag atoms, even at the room temperature , and thus lose the ability of helping the silver surface to gain the novel chem ical property. This indicates that in order to take advantage of the novel prope rties of heteronanostructures, we have to consider their longterm stabilit y and very often it is possible to choose the stable ones.
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