VARIATIONAL CALCULATIONS FOR HIGH-S-3 STATES IN HE WITH B-SPLINE BASIS FUNCTIONS

A variational configuration interaction calculation was carried out with the basis functions constructed from B splines to obtain the energies for the n3S series in He for n = 8-13. The calculated energies converge to within an uncertainty of 10(-8) au, and agree with previous highly accurate results within 10(-7) au. The accuracy of our results does not deteriorate with increasing principal quantum number. It would be expected that the more highly excited states of He can be accurately calculated by these basis functions. We also calculated the radial expectation values, the mass polarization effect, and the expectation values of delta(r1). Our present approach provided results, which are comparable to previous highly accurate results, where the coordinate r12 is explicitly used.