The Dirac equation in the algebraic approximation. II. Extended basis set calculations for hydrogenic atoms

Abstract
For pt.I see ibid., vol.17, p.L45 (1984b). The solution of the Dirac equation for hydrogen-like atoms within the algebraic approximation, that is, by using a finite basis set, is considered. It is shown that by making an appropriate choice of basis functions the problem which has been termed 'variational collapse' can be avoided. Applications using a systematic sequence of even-tempered basis sets are presented and convergence of the calculated energies within the algebraic approximation to the exact energies with increasing size of basis set is investigated.