2004/07/13 by D. Donadio M. Bernasconi, Bernasconi, D. Donadio M.
Engineering · Materials Science · Physics and Astronomy · #FOS: Physical sciences #Glass properties and applications #Materials Science (cond-mat.mtrl-sci) #Silicon Nanostructures and Photoluminescence #Thin-Film Transistor Technologies #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.cond-mat/0407323
openalex publication_date 2004/07/13 · arxiv created 2004/07/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We have studied the photoinduced transformation of small rings (3-membered)\nin amorphous silica by Car-Parrinello simulations. The process of ring opening\nleading to the formation of a couple of paramagnetic centers, namely an E' and\na non-bridging-oxygen hole center (NBOHC), has been proposed experimentally to\noccur in silica exposed to F2 laser irradiation (at 7.9 eV). By using a new\nscheme for the simulation of rare events in ab-initio molecular dynamics\n(Iannuzzi, Laio and Parrinello, Phys. Rev. Lett. 90, 238303 (2003)), we have\nidentified the transformation path for the opening of a 3-membered ring induced\nby a self-trapped triplet exciton, the migration of NBOHC and formation of a\ncouple of stable E' and NBOHC paramagnetic defects.\n