207Pb Magnetic Shielding Anisotropy in Pb(NO3)2, PbCO3, PbCrO4, PbMo04 and PbWO4 by Fourier Transform NMR

Abstract

Abstract The NMR signals of 207Pb have been observed in powder samples of Pb (NO3)2, PbCO3 , PbCrO4 , PbMoO4 and PbWO4 using a Fourier transform apparatus. All the observed signals are asymmetrical, indicating anisotropics of the magnetic shielding σ33- σ11 with values between - 56ppm for Pb(NO3)2 and - 884 ppm for PbCrO4 . The principal elements of the shielding ten­ sors σ11 , σ22 , σ33 are given relative to the Pb2+ ion at infinite dilution in H2O and can be referred to the free lead atom with the known shielding constant of earlier measurements.