AB-INITIO CALCULATION AND EXPERIMENTAL-DETERMINATION OF THE C-13 CHEMICAL SHIELDING TENSORS OF 4,4'-DIMETHOXYBIPHENYL

An ab initio calculation of the principal components of the C-13 chemi cal shielding tensors of 4,4'-dimethoxybiphenyl are reported by employ ing the ab initio GIAO approach. The geometric parameters were optimiz ed by using the Gaussian-92 program. The observed values of the C-13 N MR chemical shifts of a powdered sample were determined by using the r ecently introduced magic angle turning (MAT) experiment. Theoretical c alculations successfully reproduced the MAT experimental resonance pea ks. The results presented in this paper demonstrate the importance of using tensor information in assigning the experimental resonances. (C) 1998 Elsevier Science B.V.