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Author (up) Guardiola, R.; Navarro, J.
Title On the Lindemann Criterion for Quantum Clusters at Very Low Temperature Type Journal Article
Year 2011 Publication Journal of Physical Chemistry A Abbreviated Journal J. Phys. Chem. A
Volume 115 Issue 25 Pages 6843-6850
Keywords
Abstract The Lindemann criterion to discern the solid-like or liquid-like nature of a quantum cluster at T = 0 is discussed. A critical analysis of current Lindemann parameters is presented and a new parameter is proposed that is appropriate to study quantum clusters made of identical particles. A simple model wave function is introduced to fix the range of variation of these parameters. The model presents two extreme limits that correspond to either a liquid-like or a solid-like system; besides, it fulfills the Bose symmetry and also permits evaluations without symmetrization. Variational and diffusion Monte Carlo calculations are also performed for clusters of spinless bosons interacting through Lennard-Jones potentials. It is shown that the liquid-like or solid-like character of quantum clusters at zero temperature cannot be simply established in terms of a single parameter.
Address [Guardiola, R.; Navarro, J.] Univ Valencia, CSIC, IFIC, Valencia 46071, Spain, Email: navarro@ific.uv.es
Corporate Author Thesis
Publisher Amer Chemical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1089-5639 ISBN Medium
Area Expedition Conference
Notes ISI:000291895500012 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ elepoucu @ Serial 669
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Author (up) Navarro, J.; Guardiola, R.
Title Thermal Effects on Small Para-Hydrogen Clusters Type Journal Article
Year 2011 Publication International Journal of Quantum Chemistry Abbreviated Journal Int. J. Quantum Chem.
Volume 111 Issue 2 Pages 463-471
Keywords atomic and molecular clusters; phase transitions in clusters; structure of clusters; molecular hydrogen and isotopes
Abstract A brief review of different quantum Monte Carlo simulations of small (p-H-2)(N) clusters is presented. The clusters are viewed as a set of N structureless p-H-2 molecules, interacting via an isotropic pairwise potential. Properties as superfluidity, magic numbers, radial structure, excitation spectra, and abundance production of (p-H-2)(N) clusters are discussed and, whenever possible, a comparison with He-4(N) droplets is presented. All together, the simulations indicate that temperature has a paradoxical effect of the properties of (p-H-2)(N) clusters, as they are solid-like at high T and liquid-like at low T, due to quantum delocalization at the lowest temperature.
Address [Navarro, Jesus; Guardiola, Rafael] Univ Valencia, CSIC, IFIC, Valencia 46071, Spain, Email: navarro@ific.uv.es
Corporate Author Thesis
Publisher John Wiley & Sons Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-7608 ISBN Medium
Area Expedition Conference
Notes ISI:000285311400028 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 589
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Author (up) Warnecke, S.; Sevryuk, M.B.; Ceperley, D.M.; Toennies, J.P.; Guardiola, R.; Navarro, J.
Title The structure of para-hydrogen clusters Type Journal Article
Year 2010 Publication European Physical Journal D Abbreviated Journal Eur. Phys. J. D
Volume 56 Issue 3 Pages 353-358
Keywords
Abstract The path integral Monte Carlo calculated radial distributions of para-hydrogen clusters (p-H-2) 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.
Address [Warnecke, S.; Sevryuk, M. B.; Toennies, J. P.] Max Planck Inst Dynam & Self Org, D-37073 Gottingen, Germany, Email: navarro@ific.uv.es
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6060 ISBN Medium
Area Expedition Conference
Notes ISI:000274327600008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ elepoucu @ Serial 505
Permanent link to this record