Dipolar and J- Derived Solid State NMR Techniques and First Principles Calculations Applied to the Structure of Silicophosphates and to the Characterization of Phosphonate Grafting on Silica Nanoparticles

摘要

J-derived (HMQC, INEPT) and D-derived (double and triple resonance) experiments were applied to the detailed characterization of crystalline and amorphous silicophosphate derivatives. 31{sup left}P/29{sup left}Si and 1{sup left}H/31{sup left}P/29{sup left}Si CP MAS experiments were suitable for the description of complex silicophosphate gels, which can act as precursors for biocompatible materials. First principles calculations involving the GIPAW approach (first developed by Mauri and Pickard) were applied for the determination of CSA (29{sup left}Si, 31{sup left}P, 17{sup left}O) and quadrupolar (17{sup left}O) parameters. Excellent agreement between experimental and calculated data was obtained.