11B NMR Study of WB2

The structure of tungsten diboride, WB2, differs from those of metal diborides with AlB2- or ReB2-type structures that have been previously studied by 11B NMR spectroscopy. As opposed to the single 11B resonance reported for the metal diborides having those AlB2- or ReB2-type structures, four groups of 11B resonances are found for WB2. There is also 11B NMR spectral evidence to support the proposal by Kiesling in 1947 of an additional boron atom at the center of some of the six-membered boron rings. The 11B quadrupolar frequencies of all four groups of resonances in WB2 are all quite small (