Energy Levels of ${\mathrm{He}}^5$ and ${\mathrm{Li}}^5$

The energies of the first three levels in ${\mathrm{He}}^5$ are determined using a variational procedure. The various wave functions adopted incorporate alpha, triton, and deuteron correlations. It is determined that the ground state ($\frac{3}{2}-$) must be an alpha-neutron configuration whereas the (½-) level, which must also be described by this configuration, is not a sharp resonant state. The ($\frac{3}{2}+$) level at 16.69 Mev is shown to be a deuteron-triton configuration. The resultant energies and structures of these levels are in accord with the experimental situation. It should be stressed that our wave functions differ appreciably from the standard shell-model ones in the intermediate-coupling picture.