Anisotropic transferred hyperfine interactions in Cs2CuCl4

We report Cs-133 nuclear magnetic resonance (NMR) measurements of magnetic insulator Cs2CuCl4 in the paramagnetic phase (T >= 4.2 K) as a function of the orientation of an applied magnetic field with respect to the principal crystalline axes. The magnetic shift tensor is determined. It is found that its principal axes do not coincide with the principal axes of the crystal. The Cu-Cs dipolar interaction tensor is calculated as well. From these, we deduce the full transferred hyperfine tensor for the two inequivalent Cs sites of the unit cell. We find that the tensors are anisotropic, containing non-zero off-diagonal terms, and that the transferred hyperfine coupling between Cu electronic spins and Cs nuclei dominates the NMR shift on both Cs sites.