Improved excitation schemes for multiple-quantum magic-angle spinning for quadrupolar nuclei designed using optimal control theory

We have investigated the use of optimal control theory for the design of improved multiple-quantum excitation schemes for the popular multiple-quantum magic-angle spinning NMR experiment for quadrupolar nuclei with half-integer quadrupolar spin. The advantage of the new low-power experiments, termed ^OCFASTER, is demonstrated by sensitivity improvements approaching 50% for ⁸⁷Rb in RbClO₄ and RbNO₃ as compared to FASTER and standard strong-pulse excitation schemes.