Reaction induced by a scanning tunneling microscope: Theory and application

We develop a theoretical framework for study of chemical dynamics induced b y a scanning tunneling microscope. An analytically solvable limit of the ex pression derived for the reaction rate reveals the information content of t he voltage dependence of the observable. The theory is applied to the probl em of H-atom desorption from a silicon surface in the 4-10 V range, where d esorption is triggered by a single electronic transition into a short-lived excited state localized on the H-Si bond. The resonance lifetime is extrac ted by fitting the numerical results to an observed desorption yield versus voltage curve [Foley , Phys. Rev. Lett. 80, 1336 (1998)]. (C) 2001 America n Institute of Physics.