The polarised frozen-core approximation: Oscillator strengths for the boron isoelectronic sequence

Orbital wave functions of a large number of ns-, np-, and nd-levels of the first five members of the boron isoelectronic sequence have been calculated using a frozen-core Hartree-Fock procedure augmented by an l-dependent core polarisation potential. The calculated ionisation energies are generally in very good agreement with observations. Electric dipole oscillator strenghts have been derived from the calculated orbitals and energies and have been used to yield simple interpolation formulae for f-values of higher members of the sequence. They are expected to be of high accuracy in many cases.