Влияние адсорбированных молекул СО на электронное состояние нанопленок иттербия, выращиваемых на кремниевых подложках

Abstract

Adsorption of carbon monoxide (CO) molecules on ytterbium nanofilms with the thickness of 16 – 200 monolayers (6.1 – 76 nm) has been studied. The films are grown on single-crystal silicon substrates with the (111) surface orientation. It is shown that before the adsorption of CO molecules, ytterbium is divalent with the electronic configuration of [Xe]4f146s2. Upon the adsorption of gas molecules, a layer of trivalent ytterbium (the electronic configuration is [Xe]4f135d16s2), which is adjacent to the film surface, is formed. Evaluations of the thickness of the layer modified by adsorbed CO molecules are performed. Such evaluations have given rise to the values within 9 – 22 monolayers (3.4 – 8.4 nm).