ELECTRONIC-STRUCTURE OF ALKALI-METAL MONOLAYERS ON CU(111)

We have studied the formation of monolayer films of lithium, sodium, p otassium and cesium atoms on Cu(111) at room temperature with angle-re solved inverse and direct photoemission, and monitored the coverage-de pendent changes of the empty and occupied electronic density of states of the alkali adsorbates. All alkali metals formed 2 x 2 overlayer st ructures with characteristic two-dimensional electronic band structure s.