Structure matters: Combining X-ray scattering and ultraviolet photoelectron spectroscopy for studying organic thin films

Abstract

We discuss the relationship between organic film structure and ultraviolet photoelectron spectroscopy (UPS) data. As a useful method for obtaining detailed structural data we first introduce shortly the advantages of X-ray scattering. By combining such structural data and electronic information from UPS new insights in the fundamental principles of organic electronics can be obtained. On the basis of single layer and heterostructures we discuss the dependence of the electronic level alignment and the spectral shape of the HOMO band on the structural properties of organic thin films. Interestingly the intrinsic molecular shape of a compound has a large impact on its electronic response to changes in crystal quality.