VARIATIONAL AND DIFFUSION MONTE-CARLO STUDIES OF (H-2)(N) CLUSTERS

We present ground-state results for (H-2)N clusters, N = 6, 7, 13, and 33, obtained by variational and diffusion Monte Carlo. Optimized trial wavefunctions are used which fully incorporate Bose statistics. Included are kinetic, potential, and total energies, as well as structural data with radial distribution functions, density profiles, and moment-of-inertia distributions. Trial-function quality is excellent for the smaller clusters and still quite good at N = 33. The DMC results clearly demonstrate the liquid nature of the clusters although at N = 33, an increase in rigidity is observed. Because all clusters are liquid-like, superfluid behavior may be possible. Despite the dominance of quantum effects, the importance of five-fold symmetry is also evident and shows the mark of classical packing considerations.