Producing reactive species on Si(100), Ge(100), and Si(111) surfaces by attachments of diacetylenes

Theoretical predictions on the selectivities and mechanisms for the attachments of diacetylene on Si(100)-2 * 1, Ge(100)-2 *1, and Si(111)-7 *7 surfaces are provided. It is shown that the adsorption of diacetylene gives rise to enynic adspecies on Si(100)-2 * 1, [3]cumulenic adspecies on Si(111)-7 * 7, and both [3]cumulenic and enynic adspecies on Ge(100)-2 * 1.