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arXiv · 1101.5054

On the possible "supersolid" character of parahydrogen clusters

Fabio Mezzacapo·Massimo Boninsegni
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Abstract

We present results of a theoretical study of structural and superfluid properties of parahydrogen clusters comprising 25, 26 and 27 molecules at low temperature. The microscopic model utilized here is based on the Silvera-Goldman pair potential. Numerical results are obtained by means of Quantum Monte Carlo simulations, making use of the continuous-space Worm Algorithm. The clusters are superfluid in the low temperature limit, but display markedly different physical behaviours. For N=25 and 27, superfluidity at low temperature arises as clusters melt, i.e., become progressively liquid-like as a result of quantum effects. On the other hand, for N = 26 the cluster remains rigid and solid-like. We argue that this cluster can be regarded as a mesoscopic "supersolid". This physical picture is supported by results of simulations in which a single parahydrogen molecule in the cluster is isotopically substituted.

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Fabio Mezzacapo, Massimo Boninsegni. 2011-07-14. On the possible "supersolid" character of parahydrogen clusters. https://doi.org/10.1021/jp110524p

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