Electron affinities of boron, aluminum, gallium, indium, and thallium

The relativistic coupled-cluster method is a large four-component Gaussian-spinor basis is applied to the ionization potentials and electron affinities of group-13 elements B, Al, Ga, In, and Tl. Many shells are correlated (up to 35 electrons for Tl) to account for core effects. Calculated ionization potentials are in excellent agreement (within 0.01-0.05 eV) with experiment. The electron affinities are 0.279 eV for B (experimental 0.277+/-0.010), 0.427 eV for Al (0.44094(-0.00048)(+0.00066)), 0.301 eV for Ga (0.30+/-0.15), 0.419 eV for In (0.30+/-0.20), and 0.40+/-0.05 eV for Tl (experimental 0.20+/-0.20). The first four are in close agreement with recent multiconfiguration Dirac-Fock (MCDF) values; it is shown that the smaller affinity predicted by MCDF for Tl (0.291 eV) is due to the neglect of dynamic correlation, in particular that of the 5d electrons, which has a substantial contribution in this case. [S1050-2947(97)01812-X].