Determination of the orientation of the 13C chemical shift tensor of undoped trans-polyacetylene

Abstract By comparison of measured and simulated 13 C NMR spectra of pair-wise 13 C enriched undoped trans-polyacetylene, the orientation of the 13 C chemical shift tensor has been determined. The result is that the tensor element σ 33 is perpendicular to the molecular plane, and that the element σ 11 makes an angle of 40 ± 5° with respect to the single CC bond, and 80 ± 5° with respect to the double CC bond.