| Abstract
| - 17O NMR parameters, both the chemical shifts and the quadrupolar parameters, are calculatedfor SiO2 polymorphs using density functional theory with the generalized gradient-corrected PBE functional.The gauge including projector augmented wave (GIPAW) method (Pickard, C. J.; Mauri, F. Phys. Rev. B2001, 63, 245101) ensures the reproduction of all electron results while using computationally efficientpseudopotentials. The use of plane-waves permits fully converged calculations to be performed on structurescontaining 144 atoms in the unit cell, without the need to resort to the cluster approximation. The calculatedNMR parameters of cristobalite, quartz, coesite, and faujasite are in excellent agreement with experimentaldata. This demonstrates that density functional theory is able to reproduce with high accuracy the 17ONMR parameters in SiO2 systems. This precision is used to assign the spectrum of the zeolite ferrierite.The data calculated for SiO2 are used to confirm that no simple correlation between the chemical shift andCq NMR parameters and Si−O−Si angle exists, emphasizing the importance of predictive theories in thisfield.
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