CPL, Blaha et al: 27Al and plane wave (WIEN) calculations

Chemical Physics Letters
Volume 424, Issues 4-6 , 24 June 2006, Pages 321-326

27Al NMR experiments and quadrupolar parameter ab initio calculations: Crystallographic structure refinement of ß-Ba3AlF9

M. Body, G. Silly, C. Legein, J.-Y. Buzaré, F. Calvayrac and P. Blaha

aLaboratoire de Physique de l’Etat Condensé, CNRS UMR 6087, Institut de Recherche en Ingénierie Moléculaire et Matériaux Fonctionnels, CNRS FR 2575, Université du Maine, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9, France
bLaboratoire des Oxydes et Fluorures, CNRS UMR 6010, Institut de Recherche en Ingénierie Moléculaire et Matériaux Fonctionnels, CNRS FR 2575, Université du Maine, Avenue Olivier Messiaen, 72085 Le Mans Cedex 9, France
cLaboratoire de Physicochimie de la Matière Condensée, CNRS UMR 5617, Institut Charles Gerhardt, CNRS FR 1878, Université de Montpellier II, Place Eugène Bataillon, C.C. 03, 34095 Montpellier Cedex 5, France
dInstitute of Materials Chemistry, Vienna University of Technology A-1060 Vienna, Getreidemarkt 9/165-TC, Austria

Abstract

27Al quadrupolar parameters are determined for the three aluminium sites in ß-Ba3AlF9 from the reconstruction of experimental SATRAS and MQ-MAS NMR spectra. These quadrupolar parameters are then computed using the DFT linearized augmented plane wave method implemented in the WIEN2k code.

A fine agreement between experimental and calculated values is obtained only after optimizing the ß-Ba3AlF9 structure. The optimized structure is more satisfactory than the previously published one from a crystallographic point of view (bond lengths and angles).

This approach which allows to refine crystallographic structures especially when they lack accuracy may be extendable to other compounds containing quadrupolar nuclei.