Variational calculation of the lowestPo2andPo4states of Li andC3+by the Hylleraas method

Variational Hylleraas-type wave functions are calculated for the lowest doublet and quartet $P^{\mathrm{o}}$ states of Li and ${\mathrm{C}}^{3+}$. The (nonrelativistic) energies obtained are, for Li, -7.41008 and -5.36780 a.u., and, for ${\mathrm{C}}^{3+}$, -34.481 89 and -23.969 30 a.u., respectively. For the doublet states, the hyperfine-structure constants are also evaluated with results in good agreement with other theoretical and experimental studies.