Solid-state NMR calculations for metal oxides and gallates: Shielding and quadrupolar parameters for perovskites and related phases

The NMR parameters obtained from solid-state OFT calculations within the GIPAW approach for O-17- and Ga-69/71-sites in a range of predominantly oxide-based (group II monoxides, SrTiO3, BaZrO3, BaSnO3, BaTiO3, LaAlO3, LaGaO3, SrZrO3, MgSiO3 and Ba2In2O5), and gallate (alpha- and beta-Ga2O3, LiGaO2, NaGaO2, GaPO4 and LaGaO3) materials are compared with experimental values, with a view to the future application of a similar approach to doped phases of interest as candidate intermediate temperature solid oxide fuel cell (ITSOFC) electrolytes. Isotropic and anisotropic chemical shift parameters, quadrupolar coupling constants, and associated asymmetries are presented and analyzed. The unusual GaO5 site occurring in LaGaGe2O7 is also fully characterised. In general, it is found that the theoretical results closely track the experimental trends, though some deviations are identified and discussed, particularly in regard to quadrupolar eta(Q)-values. The high quality of the computed results suggests that this approach can be extended to study more complex and disordered phases. (C) 2010 Elsevier Inc. All rights reserved.