Quantifying the NMR spectra of Spin I 1 2 nuclei coupled to quadrupolar spin in solids

Abstract

Quantifying the NMR spectrum of spin 1/2 nucleus coupled to nuclei with spin Sgt1/2 (com newlinemonly referred to as quadrupolar spins) has remained challenging owing to the interference newline from the quadrupolar interactions during NMR experiments on spin 1/2 nucleus. While the newline availability of faster spinning probes and higher magnetic field strengths have improved the newline overall resolution and sensitivity of the NMR spectra of low sensitive spin 1/2 nuclei, ex newlinetraction of molecular constraints from such nuclei in natural abundant samples comprising newline quadrupolar spins (such as 14N (S=1) and 23Na (S=3/2)) have remained a daunting task. In newline particular, the simultaneous presence of the heteronuclear dipolar interactions and quadrupo newlinelar interactions, often complicate the interpretation of the spectral data in experiments that newline involve the application of multiple pulses on both channels. To this end, a quantitative theory newline based on the concept of Effective fields is proposed to describe the underlying spin dynam newlineics and deduce optimal conditions in experiments that involve a spin 1/2 nucleus coupled to a newline quadrupolar spin (say S=1 and 3/2). Through analytic expressions, the spectral frequencies newline and intensities observed in experiments are quantified and rigorously verified. Since molec newlineular constraints in NMR experiments are extracted through iterative fitting of experimental newline data, we believe that the proposed methodology would be beneficial in building models to newline quantify experimental data emerging from such experiments newline