P-assisted growth of molecular wires on Si (001) -2×1

Using first principles quantum mechanics (DFT/GGA with pseudopotentials) calculations, we propose a mechanism for the P-assisted auto-catalyzed chain reaction of alkene molecules on a monohydride Si (001) -2×1-H surface. This study shows that surface-incorporated P atoms can serve as an initiator and a terminator for the self-directed growth of one-dimensional molecular wires on Si(001). We first present reaction paths and energetics for creation of single Si dangling bonds by (P-associated) selective H2 desorption on the P-incorporated Si(001)-H surface, with comparison to associative H2 desorption on the clean Si(001)-H surface. The (Si-dangling bond mediated) growth of styrene molecular lines is then compared between the P-incorporated and clean Si(001) surfaces.