The configuration interaction (CI) method is one of the most commonly used
methods for the calculation of the electronic structure of atoms. The stand
ard CI method based on a linear combination of orthonormal orbitals centere
d on the nucleus has been adapted to the calculation of the structure of ex
otic atoms containing one or two electrons and a positron. Results of calcu
lations on a number of systems, including positronium hydride (PsH), e(-)Cu
, e(+)Li, e(+)Be, e(+)Cd and CuPs show both the strengths and limitations o
f the CI approach for positron binding atoms. (C) 2000 Elsevier Science B.V
. All rights reserved.