Revisiting Y2Si2O7 and Y2SiO5 polymorphic structures by 89Y MAS-NMR spectroscopy

This paper describes the Y-89 MAS-NMR spectra for all the established polymorphs of Y2Si2O7 (y, alpha, beta, gamma and delta) and Y2SiO5 (X1 and X2). The combination of our spectroscopic data with the structural information published up to now from diffraction data permits the revision and correction of mistakes which appear in the literature. Finally, the influence of different structural factors, such as yttrium coordination number and Y-O distances on the Y-89 NMR isotropic chemical shift is analyzed. (C) 2004 Elsevier Inc. All rights reserved.