Pb-207 solid state NMR studies of lead compounds

Pb-207 NMR powder pattern analysis has been applied to several lead-contain ing inorganic and organic compounds. The chemical shielding tensors obtaine d are less susceptible to systematic error than earlier studies employing m agic-angle spinning sideband analysis. Since the lead atom is very sensitiv e to its local environment, a correlation between the chemical shift and st ructure was investigated. An increase in Pb-O interatomic distance tends to shift the isotropic chemical shift (delta(iso)) to lower frequency, wherea s conversely an increase in Pb-halogen interatomic distance tends to increa se the chemical shift. As a consequence of the electronic structure of Pb2, almost all Pb-207 shielding tensors of Pb2+ species have a negative aniso tropy.