Precise Measurement of Qn Species Distributions in Modified Silicate Glass Using Phase-Adjusted Spinning Sideband NMR Experiment

Abstract

Quantification of the distribution of Q(n) species, representing the number of bridging oxygens (n) around a silicate tetrahedra in potassium disilicate glass, is achieved using the two-dimensional Phase-Adjusted Spinning Sideband (2D PASS) sequence. Furthermore, we compare the relative concentrations of each Q(n) species obtained through the PASS method with a previous study utilizing the Magic Angle Flipping (MAF) technique on the same glass composition. While MAF has been employed in prior research to enhance the precision of Q(n) species measurements in glasses, it necessitates a specialized probe capable of reorienting the rotor axis. In contrast, alternatives like MAT or 2D PASS are more appealing as they can be implemented using a conventional MAS probe. In this study, we demonstrate that the PASS experiment provides comparable accuracy to MAF while significantly reducing the required time. Graphical Abstract: [Figure not available: see fulltext.] © 2023, The Author(s), under exclusive licence to Springer Nature B.V.