Variational methods for ${}^4\mathrm{He}$ using a modern He-He potential

The two-body potential HFD-B3-FCI1 for He-He interactions proposed by Aziz and collaborators is analyzed using the variational Monte Carlo method. Complementary work using the Green’s function Monte Carlo method is presented as well. The importance of three-body effects in the description of the interactions are considered and good evidence is presented for using a potential that takes into account these effects even at the equilibrium density of systems of ${}^4\mathrm{He}$ atoms. An examination of the most usual trial functions forms employed in the studies of these systems, some experiments with other correlation factors, and some methodological notes complete this investigation.