DIET from Cryogenic Layers: Subject and Tool of Investigation

Abstract

This paper is devoted to two aspects of DIET (ESD and PSD) from Van der Waals bound layers: i) the efforts to elucidate the microscopic details of the desorption reaction, and ii) the use of DIET as a tool for the investigation of electronic excitations and properties of electronically excited states. “Simple” Van der Waals solids, namely rare gas and molecular solids, have been used for the experiments. Although the studies of desorption reactions from these samples are somehow “academic”, they nevertheless offer the chance of a detailed understanding of the different steps involved in DIET by comparing theoretical and experimental results. The examples selected for this paper are: 1) ESD of neutral particles from Ar films of various thicknesses; 2) PSD of ions from Ar films; 3) high resolution PSD of ions from solid N2. Topic 1) demonstrates how comparison of experiment and calculation can pinpoint certain desorption mechanisms, particularly when dependencies on film thickness and dopants are included in the investigation; 2) will show how DIET experiments hitherto exclusively give access to a distinct type of electronic excitation in rare gas solids (RGS), and topic 3) will finally demonstrate the aid of high spectral resolution for the detection of the nature and symmetry of electronic excitations.