Nonrelativistic CI calculations for B⁺, B, and B⁻ ground states

State of the art configuration interaction (CI) techniques are used to obtain the best possible nonrelativistic CI results for B + , B, and B − ground states using energy‐optimized basis sets of 252, 294, and 294 radial Slater‐type functions, respectively. For positive boron, E(B + ) = −24.348861 + Δ E bie = −24.348883(1) a.u.(B) with a basis set incompleteness error Δ E bie = −0.000022(1), in good agreement with the latest exponentially correlated Gaussian (ECG) result of −24.348883 a.u.(B) of Komasa et al. (Phys Rev A, 2002, 65, 042507). For neutral B, E(B) = −24.653837 −0.000024(2) = −24.653861(2), which is the most accurate ab initio estimate and lies slightly below a recent (not fully optimized) ECG result of −24.653840 a.u.(B) of Bubin et al (J Chem Phys, 2009, 131, 044128). For negative boron, E(B − ) = −24.664014 −0.000024(2) to which an energy error of −0.000001 must be added to give −24.664039(2), which is the first fully correlated ab initio result. Comparison with experimental values of ionization energy and electron affinity must await the results of corresponding relativistic calculations, in progress.