Ab initio simulations of photoinduced interconversions of oxygen deficient centers in amorphous silica -: art. no. 195504

被引：62

作者：

Donadio, D

Bernasconi, M

Boero, M

机构：

[1] Univ Milano Bicocca, Ist Nazl Fis Mat, I-20126 Milan, Italy

[2] Univ Milano Bicocca, Dipartimento Sci Mat, I-20126 Milan, Italy

[3] Angstrom Technol Partnership, Joint Res Ctr Atom Technol, Tsukuba, Ibaraki 3050046, Japan

来源：

PHYSICAL REVIEW LETTERS | 2001年 / 87卷 / 19期

关键词：

D O I：

10.1103/PhysRevLett.87.195504

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We have studied by ab initio molecular dynamics the interconversion between oxygen deficient centers (Si-Si bond, dicoordinated silicon==Si:, and El centers) induced by UV irradiation in a-SiO2. By dynamical simulations in the excited state of a periodic model of a-SiO2 we have identified the reaction path and activation barrier for the Si-Si --> =Si: interconversion. A new competitive transformation of the excited, neutral Si-Si bond into two E' centers has been identified. Our results provide strong theoretical support to the viability of these processes, proposed experimentally on the basis of optical data only.

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页数：4

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