The structure of para-hydrogen clusters
نویسندگان
چکیده
The path integral Monte Carlo calculated radial distributions of para-hydrogen clusters (p-H2)N consisting of N = 4−40 molecules interacting via a Lennard-Jones potential at T = 1.5 K show evidence for additional peaks compared to radial distributions calculated by diffusion Monte Carlo (T = 0 K) and path integral Monte Carlo at T ≤ 0.5 K. The difference in structures is attributed to quantum delocalization at the lowest temperature. The new structures at finite temperatures appear to be consistent with classical structures calculated for an effective Morse potential, which in order to account for the large zero point energy, is substantially softer than the Lennard-Jones potential. PACS. 36.40.-c Atomic and molecular clusters – 61.25.Em Molecular liquids – 67.90.+z Other topics in quantum fluids and solids
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