Observation of structure changes for Li/Cu(111) by photoemission from Li core and quantum-well states

Article

关键词: BINDING-ENERGY SHIFTS;    INTERFACE SEGREGATION ENERGIES;    ANGLE-RESOLVED PHOTOEMISSION;    METAL-METAL ADHESION;    ELECTRONIC-STRUCTURE;    PHOTOELECTRON-SPECTROSCOPY;    AL(111);    SURFACE;    NA;    OVERLAYERS;   

DOI  :  10.1103/PhysRevB.57.13192

来源: SCIE

【 摘 要 】

Via photoemission from discrete quantum-well valence states and the Li 1s core level, three different types of atom rearrangements are observed for Cu(111)/Li. In the monolayer coverage range gradual energy shifts for the core-level as well as a quantum-well state reflect a gradual lateral compression of the Li overlayer as more atoms are adsorbed. The onset of Li substitution and formation of a (2x2) structure when, at RT, monolayer Li coverage is exceeded, is monitored via the disappearance and appearance of quantum-well states characteristic of the adsorbed full monolayer of Li and the part substitutional (2x2) structure. respectively. A splitting of the Li Is emission peak into a doublet reflects the two different Li sites characteristic of the (2x2) phase. A small energy shift of the quantum-well state (25 meV) indicates that, if it is cooled (170 K), the substitutional structure is unstable with respect to Li adsorption.

【 授权许可】

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