Evaluation of the Structure of Polydiacetylene Monolayers Using Fluorescence Microscopy and Scanning Tunneling Microscopy

Abstract

This communication describes a structural study of polydiacetylene monolayers supported on highlyoriented pyrolytic graphite (HOPG). Both scanning tunneling microscopy (STM) and scanning laser confocal fluorescence microscopy were used to evaluate monolayer structure at the micrometer level. These studies demonstrate that extreme tunneling conditions (10 pA, 10 V) may be required to obtain images that are consistent with those of high-resolution fluorescence microscopy results. STM imaging using lower values of gap resistance damaged or removed the organic monolayer from the graphite surface.The correlation between optical and scanned microscopies clearly indicates the utility of STM for studying the structure of polydiacetylene films. © 1992, American Chemical Society. All rights reserved.