Solid-state Rb-87 NMR Of RbVO3. A comparison of experiments for retrievingchemical shielding and quadrupole coupling tensorial interactions

Solid-state Rb-87 NMR spectra for a powder and single crystal of RbVO3 have been acquired for the central transition at two magnetic field strengths ( 9.4 and 14.1 T) and using two single-crystal NMR probes of different design . The powder spectra have been obtained using spin-echo techniques without sample spinning because the widths of the spectra are in the range 100-150 kHz, The spectra are analyzed in terms of the chemical shielding and quadru pole coupling interactions and the parameters are compared in an evaluation of the precision for the techniques. Parameters of high precision includin g the relative orientation for the two tensors are obtained from the single -crystal spectra at 14.1 T. Finally, the orientations of the two tensors in the crystal frame are deduced from the crystal symmetry and an XRD analysi s. (C) 1999 Elsevier Science B.V, All rights reserved.