Pure Nuclear Quadrupole Resonance in Superconducting and Normal Double-hcpLa139Metal

The $\frac{3}{2}-\frac{5}{2}$ and $\frac{5}{2}-\frac{7}{2}$ pure quadrupole-resonance frequencies for the two inequivalent sites of double hcp ${}_{}{}^{139}{}_{}{}^{}\mathrm{La}$ metal have been measured in the superconducting and normal states, giving quadrupole coupling constants of 7.700(2) and 6.798(4) MHz in the normal state and shifts of about 0.10 and 0.14%, respectively, in the superconducting state. The asymmetry parameter was experimentally zero.