Spectromicroscopy Study of the Organic Molecules Utilizing Polarized Radiation

Spectromicroscopy combined with polarized synchrotron radiation is a powerful tool for imaging and characterizing the molecular properties on surface. In this work we utilized the photoemission electron microscopy (PEEM) with linear polarized radiation provided by an elliptically polarized undulator to investigate the molecular orientations of pentacene on self-assembled monolayer (SAMs) modified gold surface and to observe the cluster domain of mixed monolayers after reorganization on silver. Varying the electric vector parallel or perpendicular to the surface, the relative intensity of π* and σ* transition in carbon K-edge can be used to determine the orientation of the planar-shaped pentacene molecule or long carbon chain of carboxylic acids which are important for organic semiconductor