Classical kinetic energy, quantum fluctuation terms and kinetic-energy functionals

dc.creatorHamilton, IP
dc.creatorMosna, RA
dc.creatorDelle Site, L
dc.date2007
dc.dateAUG
dc.date2014-11-15T16:09:51Z
dc.date2015-11-26T17:20:45Z
dc.date2014-11-15T16:09:51Z
dc.date2015-11-26T17:20:45Z
dc.date.accessioned2018-03-29T00:08:20Z
dc.date.available2018-03-29T00:08:20Z
dc.identifierTheoretical Chemistry Accounts. Springer, v. 118, n. 2, n. 407, n. 415, 2007.
dc.identifier1432-881X
dc.identifier1432-2234
dc.identifierWOS:000248137900013
dc.identifier10.1007/s00214-007-0279-5
dc.identifierhttp://www.repositorio.unicamp.br/jspui/handle/REPOSIP/55962
dc.identifierhttp://www.repositorio.unicamp.br/handle/REPOSIP/55962
dc.identifierhttp://repositorio.unicamp.br/jspui/handle/REPOSIP/55962
dc.identifier.urihttp://repositorioslatinoamericanos.uchile.cl/handle/2250/1283211
dc.descriptionWe employ a recently formulated dequantization procedure to obtain an exact expression for the kinetic energy which is applicable to all kinetic-energy functionals. We express the kinetic energy of an N-electron system as the sum of an N-electron classical kinetic energy and an N-electron purely quantum kinetic energy arising from the quantum fluctuations that turn the classical momentum into the quantum momentum. This leads to an interesting analogy with Nelson's stochastic approach to quantum mechanics, which we use to conceptually clarify the physical nature of part of the kinetic-energy functional in terms of statistical fluctuations and in direct correspondence with Fisher Information Theory. We show that the N-electron purely quantum kinetic energy can be written as the sum of the (one-electron) Weizsacker term and an (N-1)-electron kinetic correlation term. We further show that the Weizsacker term results from local fluctuations while the kinetic correlation term results from the nonlocal fluctuations. We then write the N-electron classical kinetic energy as the sum of the (one-electron) classical kinetic energy and another (N-1)-electron kinetic correlation term. For one-electron orbitals (where kinetic correlation is neglected) we obtain an exact (albeit impractical) expression for the noninteracting kinetic energy as the sum of the classical kinetic energy and the Weizsacker term. The classical kinetic energy is seen to be explicitly dependent on the electron phase, and this has implications for the development of accurate orbital-free kinetic-energy functionals. Also, there is a direct connection between the classical kinetic energy and the angular momentum and, across a row of the periodic table, the classical kinetic energy component of the noninteracting kinetic energy generally increases as Z increases. Finally, we underline that, although our aim in this paper is conceptual rather than practical, our results are potentially useful for the construction of improved kinetic-energy functionals.
dc.description118
dc.description2
dc.description407
dc.description415
dc.languageen
dc.publisherSpringer
dc.publisherNew York
dc.publisherEUA
dc.relationTheoretical Chemistry Accounts
dc.relationTheor. Chem. Acc.
dc.rightsfechado
dc.rightshttp://www.springer.com/open+access/authors+rights?SGWID=0-176704-12-683201-0
dc.sourceWeb of Science
dc.subjectkinetic-energy functionals
dc.subjectdequantization
dc.subjectfisher information theory
dc.subjectNelson's stochastic mechanics
dc.subjectquantum fluctuations
dc.subjectclassical kinetic functional
dc.subjectFull Weizsacker Correction
dc.subjectThomas-fermi Theory
dc.subjectDensity-functionals
dc.subjectElectron-densities
dc.subjectFisher Information
dc.subjectVon Weizsacker
dc.subjectAtom
dc.subjectSystems
dc.subjectImprovements
dc.subjectDerivation
dc.titleClassical kinetic energy, quantum fluctuation terms and kinetic-energy functionals
dc.typeArtículos de revistas


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