title: Lightweight hydrogen-storage material Mg(0.65)Sc(0.35)D2 studied with 2H and 2H-{45Sc} MAS NMR exchange spectroscopy.
abstract: Using double-quantum (2)H MAS NMR with (45)Sc recoupling and Bloch-Siegert compensated (2)H-{(45)Sc} TRAPDOR we have identified the overlapping NMR signals of deuterium with and without scandium neighbors in Mg(0.65)Sc(0.35)D(2), a candidate lightweight material for hydrogen storage. At room temperature we also observe a third type of mobile deuterium. Deuterium mobility among the three NMR-distinct sites has been investigated by means of one-and two-dimensional exchange spectroscopy (Exsy). Complete deuterium exchange within 0.1s is observed, which indicates that the three NMR-distinct sites are close together in the crystal lattice. The weak temperature- and MAS-rate dependences observed in Exsy are indicative for a combination of chemical exchange and spin diffusion.
authors.affiliation: Inorganic Materials Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands.
authors.forename: S
authors.initials: S
authors.lastname: Srinivasan
authors.forename: P C M M
authors.initials: PC
authors.lastname: Magusin