화학공학소재연구정보센터
Journal of Physical Chemistry A, Vol.119, No.49, 11847-11861, 2015
Solid-State Sr-87 NMR Spectroscopy at Natural Abundance and High Magnetic Field Strength
Twenty-five strontium-containing solids were characterized via Sr-87 NMR spectroscopy at natural abundance and high magnetic field strength (B-0 = 21.14 T). Strontium nuclear quadrupole coupling constants in these compounds are sensitive to the strontium site symmetry and range from 0 to 50.5 MHz. An experimental Sr-87 chemical shift scale is proposed, and available data indicate a chemical shift range of approximately 550 ppm, from -200 to +350 ppm relative to Sr2+(aq). In general, magnetic shielding increased with strontium coordination number. Experimentally measured chemical shift anisotropy is reported for stationary samples of solid powdered SrCl2 center dot 6H(2)O, SrBr2 center dot 6H(2)O, and SrCO3, with delta(aniso)(Sr-87) values of +28, +26, and -65 ppm, respectively. NMR parameters were calculated using CASTE?, a gauge including projector augmented wave (GIPAW) DFT-based program, which addresses the periodic nature of solids using plane-wave basis sets. Calculated NMR parameters are in good agreement with those measured.