𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Oxygen vacancies in amorphous silica: structure and distribution of properties

✍ Scribed by P.V. Sushko; S. Mukhopadhyay; A.M. Stoneham; A.L. Shluger

Publisher
Elsevier Science
Year
2005
Tongue
English
Weight
231 KB
Volume
80
Category
Article
ISSN
0167-9317

No coin nor oath required. For personal study only.

✦ Synopsis

We used an ab initio embedded cluster method to study and compare three charged states of the Si-Si dimer configurations of oxygen vacancies in -quartz and amorphous silica. The Si-Si bond in the neutral vacancy remains largely the same in both crystalline and amorphous SiO 2 . In -quartz the positively charged dimer E' centre exists only as a metastable configuration, whereas in amorphous silica stable dimer configuration can be formed at favorable precursor sites. Our results demonstrate that negatively charged dimer oxygen vacancies can be formed in -quartz.

πŸ“œ SIMILAR VOLUMES

A first principles study of positively c
A first principles study of positively charged oxygen vacancies migration in pure and Ge-doped amorphous silica
✍ Richard Nicolas; Girard Sylvain; Martin-Samos Layla; Boukenter Aziz; Ouerdane Yo πŸ“‚ Article πŸ“… 2008 πŸ› Elsevier Science 🌐 English βš– 225 KB

Using first principles calculations in a periodic amorphous silica supercell, we calculated the energies and the migration barriers of a positively charged oxygen vacancy in pure and germanium-doped silica. The results show that the puckered and dimer structures of the Si-E 0 and of the Ge-E 0 cente

Ordering of Oxygen Vacancies and Magneti
Ordering of Oxygen Vacancies and Magnetic Properties in La0.5Ca0.5MnO3βˆ’Ξ΄ (0≀δ≀0.5)
✍ J.M. GonzΓ‘lez-Calbet; E. Herrero; N. Rangavittal; J.M. Alonso; J.L. MartΔ±&#x πŸ“‚ Article πŸ“… 1999 πŸ› Elsevier Science 🌐 English βš– 827 KB

The study by electron di4raction and high resolution electron microscopy of several samples of the system La 0.5 Ca 0.5 MnO 3؊ , apart from strikingly con5rming the correctness of the orthorhombic perovskite-related unit cell of a+a c (2, b+a c (2, c+2a c for 04 40.25, points to the existence of thr