¹³C chemical shielding anisotropies of metal acetates

The ¹³C chemical shielding anisotropies are reported for a series of common diamagnetic acetates. Neither the carboxyl nor the methyl tensors are axially symmetric in all compounds studied and the values measured are in reasonable agreement with previous measurements. The CP-MAS spectra of calcium and lead acetate give three or more lines in the carboxyl region and were not analyzed. The lithium, aluminum, sodium, and lanthanum acetate spectra are considerably broadened by the metal-carbon dipole-dipole interaction which may be suppressed by slow magic-angle spinning. Use of high magnetic fields to suppress the relative importance of the metal-carbon dipolar interaction and to accentuate the chemical-shift anisotropy is also illustrated.