ELECTRON-AFFINITIES OF BORON, ALUMINUM, GALLIUM, INDIUM, AND THALLIUM

The relativistic coupled-cluster method is a large four-component Gaus sian-spinor basis is applied to the ionization potentials and electron affinities of group-13 elements B, Al, Ga, In, and Tl. Many shells ar e 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 particu lar that of the 5d electrons, which has a substantial contribution in this case. [S1050-2947(97)01812-X].