Combining STMAS and CRAMPS NMR spectroscopy: High-resolution HETCOR NMR spectra of quadrupolar and 1~H nuclei in solids

摘要

High-resolution two-dimensional (2D) heteronuclear correlation spectra between half-integer quadrupolar and IH nuclei have been obtained combining _atellite Transition Magic-Angle _pinning (_TMA_) and wPMLG3 CRAMP_ methods. The experiments use split-ti versions of DQ/DQF-_TMA_ adapted to 3/2 and 5/2 spins to obtain a 23~Na and ~27A1 isotropic dimension, respectively. Transfer of magnetization from quadrupolar nuclei to protons has been achieved by cross-polarization, and high-resolution IH spectra have been recorded using the wPMLG3 decoupling during the t2 evolution period. The performance of the pulse sequences have been tested on the templated microporous aluminophosphate IsT-1 and triso_dium citrate employing a Bo field of 9.4 T.