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dc.contributor.authorCazorla Silva, Claudio
dc.contributor.authorBoronat Medico, Jordi
dc.contributor.otherUniversitat Politècnica de Catalunya. Departament de Física i Enginyeria Nuclear
dc.date.accessioned2015-02-20T15:30:21Z
dc.date.available2015-02-20T15:30:21Z
dc.date.created2015-01-07
dc.date.issued2015-01-07
dc.identifier.citationCazorla, C.; Boronat, J. First-principles modeling of quantum nuclear effects and atomic interactions in solid He-4 at high pressure. "Physical review B: condensed matter and materials physics", 07 Gener 2015, vol. 91, núm. 2, p. 1-9.
dc.identifier.issn1098-0121
dc.identifier.urihttp://hdl.handle.net/2117/26453
dc.description.abstractWe present a first-principles computational study of solid He-4 at T = 0 K and pressures up to similar to 160 GPa. Our computational strategy consists in using van der Waals density functional theory (DFT-vdW) to describe the electronic degrees of freedom in this material, and the diffusion Monte Carlo (DMC) method to solve the Schrodinger equation describing the behavior of the quantum nuclei. For this, we construct an analytical interaction function based on the pairwise Aziz potential that closely matches the volume variation of the cohesive energy calculated with DFT-vdW in dense helium. Interestingly, we find that the kinetic energy of solid He-4 does not increase appreciably with compression for P >= 85 GPa. Also, we show that the Lindemann ratio in dense solid He-4 amounts to 0.10 almost independently of pressure. The reliability of customary quasiharmonic DFT (QH DFT) approaches in describing quantum nuclear effects in solids is also studied. We find that QH DFT simulations, although provide a reasonable equation of state in agreement with experiments, are not able to reproduce correctly these critical effects in compressed He-4. In particular, we disclose huge discrepancies of at least similar to 50% in the calculated He-4 kinetic energies using both the QH DFT and present DFT-DMC methods.
dc.format.extent9 p.
dc.language.isoeng
dc.rightsAttribution-NonCommercial-NoDerivs 3.0 Spain
dc.rights.urihttp://creativecommons.org/licenses/by-nc-nd/3.0/es/
dc.subjectÀrees temàtiques de la UPC::Física
dc.subject.lcshMonte Carlo method
dc.subject.lcshX-ray diffractometer
dc.subject.lcshEquations of state
dc.subject.lcshQuantum solids
dc.subject.otherMonte-Carlo algorithms
dc.subject.otherAugmented-wave method
dc.subject.otherX-Ray-diffraction
dc.subject.otherEquation-of-state
dc.subject.otherGround-state
dc.subject.otherMolecular-hydrogen
dc.subject.otherMegabar pressures
dc.subject.otherSingle-crystal
dc.subject.otherDense helium
dc.subject.otherTemperature
dc.titleFirst-principles modeling of quantum nuclear effects and atomic interactions in solid He-4 at high pressure
dc.typeArticle
dc.subject.lemacMontecarlo, Mètode de
dc.subject.lemacRaigs X -- Difracció
dc.subject.lemacEquacions d'estat
dc.contributor.groupUniversitat Politècnica de Catalunya. SIMCON - First-principles approaches to condensed matter physics: quantum effects and complexity
dc.identifier.doi10.1103/PhysRevB.91.024103
dc.relation.publisherversionhttp://journals.aps.org/prb/abstract/10.1103/PhysRevB.91.024103
dc.rights.accessOpen Access
local.identifier.drac15446784
dc.description.versionPostprint (published version)
local.citation.authorCazorla, C.; Boronat, J.
local.citation.publicationNamePhysical review B: condensed matter and materials physics
local.citation.volume91
local.citation.number2
local.citation.startingPage1
local.citation.endingPage9


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