Surface reaction of alkynes and alkenes with H-Si(111): A density functional theory study

Noboru Takeuchi, Yosuke Kanai, Annabella Selloni

Research output: Contribution to journalArticle

82 Scopus citations

Abstract

Recent experiments on the addition of alkene and alkyne molecules to H-terminated silicon surfaces have provided evidence for a surface chain reaction initiated at isolated Si dangling bonds and involving an intermediate carbon radical state, which, after abstraction of a hydrogen atom from a neighboring Si-H unit, transforms into a stable adsorbed species plus a new Si dangling bond. Using periodic density functional theory (DFT) calculations, together with an efficient method for determining reaction pathways, we have studied the initial steps of this chain reaction for a few different terminal alkynes and alkenes interacting with an isolated Si dangling bond on an otherwise H-saturated Si(111) surface. Calculated minimum energy pathways (MEPs) indicate that the chain mechanism is viable in the case of C2H 2, whereas for C2H4 the stabilization of the intermediate state is so small and the barrier for H-abstraction so (relatively) large that the molecule is more likely to desorb than to form a stable adsorbed species. For phenylacetylene and styrene, stabilization of the intermediate state and decrease of the H-abstraction barrier take place. While a stable adsorbed species exists in both cases, the overall heat of adsorption is larger for the alkyne molecules.

Original languageEnglish (US)
Pages (from-to)15890-15896
Number of pages7
JournalJournal of the American Chemical Society
Volume126
Issue number48
DOIs
StatePublished - Dec 8 2004

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

Fingerprint Dive into the research topics of 'Surface reaction of alkynes and alkenes with H-Si(111): A density functional theory study'. Together they form a unique fingerprint.

  • Cite this