The method of configuration interaction is applied to the 23Sstate of the helium atom. The final set of 80 configurations gives an energy of mdash;2.1752246 a.u. for this state without complete optimization of all the variational parameters. This value is to be compared with Pekeris' extrapolated value of mdash;2.1752294 and his 125 function basis value of mdash;2.1752210. Thus, it is concluded that hope still exists to obtain wave functions by the configuration interation method which would compare favorably with Pekeris' extrapolated values.
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