Carbon-13 chemical shielding tensors in acetic acid.
High resoln. double resonance methods were employed to study the anisotropic 13C chem. shifts in a single crystal of acetic acid. The principal values in ppm relative to an external ref. of liq. benzene are -136 +- 2, -52 +- 2 and 24 +- 2 for the carboxyl carbon and 89 +- 2, 102 +- 2 and 123 +- 2 for the methyl carbon. The moxt shielded element of the carboxyl tensor is perpendicular to the mol. plane, the least shielded element makes an angle of 47 Deg with the C-C bond direction. The most shielded element of the methyl tensor is in the mol. plane, making an angle of 19 Deg with the C-C bond direction.
Dieser Eintrag ist freigegeben.