title: Electron trapping at point defects on hydroxylated silica surfaces.
abstract: The origin of electron trapping and negative charging of hydroxylated silica surfaces is predicted based on accurate quantum-mechanical calculations. The calculated electron affinities of the two dominant neutral paramagnetic defects, the nonbridging oxygen center, identical with Si-O*, and the silicon dangling bond, identical with Si*, demonstrate that both defects are deep electron traps and can form the corresponding negatively charged defects. We predict the structure and optical absorption energies of these diamagnetic defects.
authors.affiliation: Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, via R. Cozzi, 53-20125 Milano, Italy.
authors.forename: Livia
authors.initials: L
authors.lastname: Giordano
authors.forename: Peter V
authors.initials: PV
authors.lastname: Sushko
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Pacchioni
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Shluger