Gervais, C. and MacKenzie, K.J.D. and Smith, M.E. (2001) Multiple magnetic field 27Al solid-state NMR study of the calcium aluminates CaAl4O7 and CaAl12O19. Magnetic Resonance in Chemistry, 39 (1). pp. 23-28. ISSN 0749-1581
Full text not available from this repository.Abstract
27Al NMR spectra are reported for the crystalline aluminates CaAl4O7 and CaAl12O19 at three magnetic fields (8.45, 11.7, 14.1 T) using conventional and 3Q fast magic angle spinning (MAS) NMR techniques. For CaAl4O7 two distinct aluminate tetrahedra are observed, both of which are in triclusters and can be assigned on the basis of the structural distortion index. The NMR interaction parameters deduced for these units allow useful comparison with other tetrahedra in triclusters. The spectra from CaAl12O19 can be simulated using five distinct signals (3 × AlO6, 1 × AlO5, 1 × AlO4) which are assigned to specific sites within the structure. Comparison is made with previous NMR studies of CaAl12O19 and with the structurally closely related phase SrAl12O19. Copyright © 2001 John Wiley & Sons, Ltd.