Ab initio calculations of the ground-state electron affinities of gallium and indium

The ground-state electron affinities of gallium and indium have been obtain ed by comparing electron affinities calculated at the numerical multiconfig uration Hartree-Fock level and at coupled-cluster levels using Gaussian bas is sets. The relativistic corrections to the electron affinities have been calculated at the multireference valence-universal Fock-space coupled-clust er level. The obtained electron affinity for indium of 0.371(15) eV is in g ood agreement with the experimental value of 0.404(9) eV. For gallium, the present calculated electron affinity of 0.297(13) eV is 0.133 eV smaller th an the recent experimental value of 0.43(3) eV.