The partial 1H NMR spectra of Al–OH and molecular H 2O in hydrous aluminosilicate glasses: Component-Resolved analysis of 27Al– 1H cross polarization and 1H spin-echo MAS NMR spectra

Abstract

The Component-Resolved methodology was applied to 1H spin-echo and 27Al– 1H cross polarization (CP) MAS NMR data of aluminosilicate glasses. The method was able to resolve two components with different T2 relaxation rates, hydroxyl groups (OH) and molecular water (H 2O mol), from the spin-echo data and to determine partial spectra and the relative abundances of OH and H 2O mol. The algorithm resolved two to three components with different 27Al– 1H CP dynamics from the 27Al– 1H cross polarization data; the obtained partial NMR spectra for Al–OH are in excellent agreement with those obtained previously from the difference spectra between spectra with various contact times and confirm previous quantitative results and models for the Al–OH, Si–OH and H 2O mol speciation (Malfait and Xue, 2010).