Infrared spectra from the deuterium substituted ethenes, H2CCD2 and D2CCD2 adsorbed on Pt(111) at 360 K, and these plus HDCCDH on a finely-divided Pt/SiO2 catalyst at ca. 300 K, allow a detailed analysis of the spectra from the isotopically-substituted ethylidynes. The RAIRS spectra from Pt(111) and the transmission spectra from Pt/SiO2 (limited to > 1300 cm-1) are complementary in providing information about the vCC/δCH3/δCD3 and the vCH/vCD regions respectively. The transmission spectra on Pt/SiO2 also provide information about additional di-σ and π-adsorbed species on the finely-divided catalyst. The spectra from H2CCD2 show that there is isotopic scrambling between the adsorbed ethylidyne species, possibly mediated by the coexisting PtH/PtD species. There are indications that this does not apply to the nondissociative di-σ adsorbed species. © 1990.
|Number of pages
|Journal of Electron Spectroscopy and Related Phenomena
|Published - 1990