title: The WURST kind of pulses in solid-state NMR.
abstract: WURST pulses (wideband, uniform rate, smooth truncation) were first introduced two decades ago by Kupče and Freeman as a means of achieving broadband adiabatic inversion of magnetisation for solution-state (13)C decoupling at high magnetic field strengths. In more recent years these pulses have found use in an increasingly diverse range of applications in solid-state NMR. This article reviews a number of recent developments that take advantage of WURST pulses, including broadband excitation, refocusing and cross polarisation for the acquisition of ultra-wideline powder patterns, signal enhancement for half-integer and integer spin quadrupolar nuclei, spectral editing, direct and indirectly observed (14)N overtone MAS, and symmetry-based homonuclear recoupling. Simple mathematical descriptions of WURST pulses and some brief theory behind their operation in the adiabatic and non-adiabatic regimes are provided, and various practical considerations for their use are also discussed.
authors.affiliation: Institute for Frontier Materials, Deakin University, Waurn Ponds Campus, Geelong, Victoria 3220, Australia. Electronic address: luke.odell@deakin.edu.au.
authors.forename: Luke A
authors.initials: LA
authors.lastname: O'Dell
mesh_terms: D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D013223:Statistics as Topic
keywords: Adiabatic pulses; Broadband decoupling; Cross polarisation; Overtone NMR; Quadrupolar nuclei; Recoupling; Signal enhancement; Ultra-wideline NMR; WURST pulses