Structure of small molecular hydrogen clusters

The ground state energies and structural properties of small (H₂) _N ,N=2?7, are calculated using the variational Monte Carlo method. These wavefunctions include both short- and long-range correlation effects that are important in the binding of van der Waals clusters. We have investigated these clusters using shadow wavefunctions and found that the coupling to shadow variables raises the energy in all cases, implying that the ground states of these small clusters are properly described as quantum liquids rather than solid structures.