The atomic-beam, laser-rf double-resonance technique has been used to make precise measurements of the dipole and quadrupole hyperfine constants of the ${}_{}{}^3{}_{}{}^{}H_{6,5,4}^{}{}_{}{}^{}$ and ${}_{}{}^3{}_{}{}^{}F_{4,3,2}^{}{}_{}{}^{}$ states of the $4f^{12}6s^2$ configuration of ${}_{}{}^{167}{}_{}{}^{}\mathrm{Er}$ I. The hyperfine integrals $〈r^{-3\mathrm{}}〉$ are extracted and compared with published ab initio calculations.

• Received 23 May 1983

DOI:https://doi.org/10.1103/PhysRevA.28.3402