The" N chemical shift tensors of uracil are reported using I5N powder pattem techniques. The principal values of the I5N uracil tensors are obtained from the spectra of [l-'5N] uracil and [3-'jN] uracil, and the tensor orientations are determined from the spectrum of [1, 3-'5N2, 2-'3C]~ ra~ i1 by including the effects of the direct dipolar interaction in the spectral fitting routine. Ambiguities in the orientational assignments, which arise from the axial symmetry ...
