NMR PROPERTIES OF HCP RU METAL - 1ST DETECTION OF THE RU-99 AND RU-101 NMR IN A PARAMAGNETIC SOLID

Results of nuclear magnetic resonance (NMR) measurements on hexagonal close-packed Ru metal are presented. The field spectra of both isotopes, having a nuclear spin I of 5/2, show a shape characteristic for quadrupolar disturbed NMR. From a simulation of these spectra, the electric field gradient V(zz) has been determined to be (37 +/- 0.5) x 10(-13) esu/cm3 in agreement with recent band structure calculations. The Knight shift tensor elements deduced from the spectra are K(x) = K(y) = 0.46 +/- 0.02% and K(z) = 0.56 +/- 0.02%. These rather high and positive shifts are completely in line with that of the neighboring elements in the periodic system and have primarily to be ascribed to the Van Vleck contribution. This part of the Knight shift is also responsible for the rather strong anisotropy, that has been found.