PHOTON-STIMULATED DESORPTION OF METHANOL ON SI(111)7 X 7 AND SI(100)2X-1 AT THE C-1S AND O 1S THRESHOLDS

Photostimulated desorption experiments have been performed on deuterat ed methanol adsorbed on Si(111) 7 x 7 and Si(100) 2 x 1 at the C Is an d O Is thresholds. D+ and the masses of the series CDx+ are produced i n the photofragmentation process in both energy ranges. A comparison h as been made with the photofragmentation spectra of methanol in the ga s phase and two different desorption mechanisms have been hypothesized for the desorption of D+ and higher masses from the silicon surfaces at the C Is threshold. (C) 1997 Elsevier Science B.V.