Thermal and photo-induced oxidation of CH2 on Cu(100)

The oxidation of the CH2 species produced by thermal and photo-induced diss ociation of CH2I2 has been followed by X-ray and ultraviolet photoelectron spectroscopies and temperature programmed spectroscopy. Preadsorbed oxygen atoms hindered the thermal dissociation of CH2I2. The dominant pathway of C H2 formed above 200 K is its coupling into C2H4 which interacted with adsor bed O atoms. Formaldehyde formation was not observed. However, CH2 produced by illumination of adsorbed CH2I2 at similar to 100 K combined with adsorb ed O to give CH2O. (C) 1999 Elsevier Science B.V. All rights reserved.