The energies of ${}^3\mathrm{H}$, ${}^3\mathrm{He}$, and ${}^4\mathrm{He}$ ground states, the ${\frac{3}{2}}^{{}^{-}}$ and ${\frac{1}{2}}^{{}^{-}}$ scattering states of ${}^5\mathrm{He}$, the ground states of ${}^6\mathrm{He}$, ${}^6\mathrm{Li}$, and ${}^6\mathrm{Be}$, and the $3^{+}$ and $0^{+}$ excited states of ${}^6\mathrm{Li}$ have been accurately calculated with the Green's function Monte Carlo method using realistic models of two- and three-nucleon interactions. The splitting of the $A=3\mathrm{}$ isospin $T=\frac{1}{2}$ and $A=6\mathrm{}$ isospin $T=1\mathrm{}$, $J^{\pi }{=0\mathrm{}}^{+}$ multiplets is also studied. The observed energies and radii are generally well reproduced, however, some definite differences between theory and experiment can be identified.

• Received 11 January 1995

DOI:https://doi.org/10.1103/PhysRevLett.74.4396