| Issue |
J. Phys. Colloques
Volume 46, Number C8, Décembre 1985
Third International Conference on the Structure of Non-Crystalline Materials
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|---|---|---|
| Page(s) | C8-113 - C8-117 | |
| DOI | https://doi.org/10.1051/jphyscol:1985814 | |
J. Phys. Colloques 46 (1985) C8-113-C8-117
DOI: 10.1051/jphyscol:1985814
A MAS NMR STUDY OF THE STRUCTURE OF AMORPHOUS ALUMINA FILMS
R. Dupree1, I. Farnan1, A.J. Forty1, S. El-Mashri2 and L. Bottyan31 Physics Department, University of Warwick, Coventry CV4 7AL, U.K.
2 Libyan Atomic Energy Establishment, Tripoli, Libya.
3 Central Research Institute for Physics, H-1525 Budapest, P.O.B. 49, Hungary.
Résumé
Des films d'alumine amorphe obtenus par dépôts anodiques ont été étudiés par MAS-RMN de Al27. La méthode de préparation fait varier la coordination de l'aluminium de 4 à 6,5 . Environ 20 % de Al se trouve dans des sites comparables à ceux de l'alumine cristalline. Le reste de Al se trouve dans des sites fortement distordus localement. La dispersion sur la longueur des liaisons Al-O est de l'ordre de 10%.
Abstract
Magic Angle Spinning 27Al N.M.R. data on some anodically formed amorphous alumina films are presented. The spectra show that aluminium has 6,5 and 4-fold coordinations in these films whose proportions depend upon the method of preparation of the film. About 20% of the aluminium is at sites with relatively high symmetry comparable with crystalline aluminas, the remaining aluminium has more distorted surroundings. The data imply an Al-O bond length variation of about 10% in these films.