Interface Excitons in Krmnen Clusters : The Role of Electron Affinity in the Formation of Electronic Structure

Abstract

The formation of the electronic structure of small Kr_m clusters (m<150) embedded inside Ne_N clusters (1200 Delta_1i . Kr clusters comprising up to 70 atoms do not exhibit bulk absorption bands. We suggest that this is due to the penetration of the interface excitons into the Kr_m cluster volume, because of the negative electron affinity of surrounding Ne atoms. From the energy shift of the interface absorption bands with cluster size an unexpectedly large penetration depth of delta_1i =7.0+/-0.1 A is estimated, which can be explained by the interplay between the electron affinities of the guest and the host cluster.