The research project of this Presidential Faculty Fellow is in the general area of analytical and surface chemistry and in the subfield of surface microscopy. During the five-year tenure of this award, Professor Hamers and his students will utilize scanning tunneling microscopy (STM) and related techniques to observe, understand, and control the surface chemistry of solid state materials at an atomic level. These important goals will be pursued by using STM techniques to identify molecular surface species; through the integration of STM with other chemically sensitive techniques such as infrared absorption spectroscopy; through the development of novel scanned probe techniques which could provide new methods for achieving elemental and/or functional group identification on nanometer distance scales; and by making use of the STM tip as an active tool for inducing chemical changes in this distance domain. %%% The successful attainment of the goals of this project should give rise to new techniques for the atomic-scale characterization of solid surfaces as well as innovative chemical insights regarding surface reactions which are of immense technological significance. Additionally, this Presidential Faculty Fellowship should significantly assist Professor Hamers in the continuing development of his vital and productive program of research and research training.