title: Quadrupolar transients, cosine correlation functions, and two-dimensional exchange spectra of non-selectively excited spin-3/2 nuclei: A (7)Li NMR study of the superionic conductor lithium indium phosphate.
abstract: Cos-cos stimulated echoes of non-selectively excited spin-3/2 nuclei were not exploited in studies of slow motional processes in solids and solid-like samples, so far. Based on a theoretical analysis of the quadrupolar transients which hitherto obviously precluded the application of such echoes, their utility is demonstrated for the example of (7)Li NMR on the polycrystalline fast ion conductor lithium indium phosphate. Quadrupolar transients can adversely affect the shape of two- and three-pulse echo spectra and strategies are successfully tested that mitigate their impact. Furthermore, by means of suitably adapted cos-cos echo sequences an effective suppression of central-line contributions to the NMR spectra is achieved. By combining cos-cos and sin-sin datasets static two-dimensional exchange spectra were recorded that display quadrupolarly modulated off-diagonal intensity indicative of ionic motion.
authors.affiliation: Fakultät Physik, Technische Universität Dortmund, 44221 Dortmund, Germany. Electronic address: michael.storek@tu-dortmund.de.
authors.forename: M
authors.initials: M
authors.lastname: Storek
authors.affiliation: Fakultät Physik, Technische Universität Dortmund, 44221 Dortmund, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Böhmer
keywords: Quadrupolar nuclei; Solid-state NMR; Stimulated spin echoes; Two-dimensional spectroscopy