Energetics and electronic structure of UAl4 with point defects

Autores
Kniznik, Laura; Alonso, Paula Regina; Gargano, Pablo Hugo; Rubiolo, Gerardo Hector
Año de publicación
2015
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
UAl4 ideal and defect structures were studied within the framework of the Density Functional Theory. The structural and magnetic ordering of UAl4 in paramagnetic, ferromagnetic, and antiferromagnetic states have been investigated, within the collinear and non-collinear spin approximation, using the GGA model, as embedded in the program package VASP. An antiferromagnetic ð011Þ layer structure with spins aligned to the [010] direction was found to be energetically preferred. The analysis of density of states and bonding charge density point out that the bonding mechanism consists primarily of band mixing between the U 5f and Al 3p states. Supercells were built from UAl4 unit cells with the established magnetic structure. For those supercells we calculated the energy of formation of vacancies and antisite defects taking into account the existence of three distinct aluminum sites. Point defect formation energies, local lattice relaxations, as well as the defect induced magnetic ordering and electronic density redistribution, are discussed. It is shown that antiferromagnetism is locally broken. Al antisites and U antisites in Al 4e Wyckoff positions are the constitutional point defects in Al-rich and U-rich oI20 UAl4, respectively. In this way we have presented here the first set of data which makes it possible to discuss and quantify the point defects concentrations in the experimental composition range for existence of this uranium aluminide.
Fil: Kniznik, Laura. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Comisión Nacional de Energía Atómica; Argentina
Fil: Alonso, Paula Regina. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Comisión Nacional de Energía Atómica; Argentina
Fil: Gargano, Pablo Hugo. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de San Martín. Instituto Sabato; Argentina
Fil: Rubiolo, Gerardo Hector. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
Materia
Actinide Materials And Compounds
Dft Calculations
Crystal Structure
Electronic Properties
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/41789

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network_name_str CONICET Digital (CONICET)
spelling Energetics and electronic structure of UAl4 with point defectsKniznik, LauraAlonso, Paula ReginaGargano, Pablo HugoRubiolo, Gerardo HectorActinide Materials And CompoundsDft CalculationsCrystal StructureElectronic Propertieshttps://purl.org/becyt/ford/1.3https://purl.org/becyt/ford/1UAl4 ideal and defect structures were studied within the framework of the Density Functional Theory. The structural and magnetic ordering of UAl4 in paramagnetic, ferromagnetic, and antiferromagnetic states have been investigated, within the collinear and non-collinear spin approximation, using the GGA model, as embedded in the program package VASP. An antiferromagnetic ð011Þ layer structure with spins aligned to the [010] direction was found to be energetically preferred. The analysis of density of states and bonding charge density point out that the bonding mechanism consists primarily of band mixing between the U 5f and Al 3p states. Supercells were built from UAl4 unit cells with the established magnetic structure. For those supercells we calculated the energy of formation of vacancies and antisite defects taking into account the existence of three distinct aluminum sites. Point defect formation energies, local lattice relaxations, as well as the defect induced magnetic ordering and electronic density redistribution, are discussed. It is shown that antiferromagnetism is locally broken. Al antisites and U antisites in Al 4e Wyckoff positions are the constitutional point defects in Al-rich and U-rich oI20 UAl4, respectively. In this way we have presented here the first set of data which makes it possible to discuss and quantify the point defects concentrations in the experimental composition range for existence of this uranium aluminide.Fil: Kniznik, Laura. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Comisión Nacional de Energía Atómica; ArgentinaFil: Alonso, Paula Regina. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Comisión Nacional de Energía Atómica; ArgentinaFil: Gargano, Pablo Hugo. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de San Martín. Instituto Sabato; ArgentinaFil: Rubiolo, Gerardo Hector. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaElsevier Science2015-08info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/41789Kniznik, Laura; Alonso, Paula Regina; Gargano, Pablo Hugo; Rubiolo, Gerardo Hector; Energetics and electronic structure of UAl4 with point defects; Elsevier Science; Journal of Nuclear Materials; 466; 8-2015; 539-5500022-3115CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/url/https://www.sciencedirect.com/science/article/pii/S0022311515301859info:eu-repo/semantics/altIdentifier/doi/10.1016/j.jnucmat.2015.08.049info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:00:50Zoai:ri.conicet.gov.ar:11336/41789instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-29 10:00:50.613CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Energetics and electronic structure of UAl4 with point defects
title Energetics and electronic structure of UAl4 with point defects
spellingShingle Energetics and electronic structure of UAl4 with point defects
Kniznik, Laura
Actinide Materials And Compounds
Dft Calculations
Crystal Structure
Electronic Properties
title_short Energetics and electronic structure of UAl4 with point defects
title_full Energetics and electronic structure of UAl4 with point defects
title_fullStr Energetics and electronic structure of UAl4 with point defects
title_full_unstemmed Energetics and electronic structure of UAl4 with point defects
title_sort Energetics and electronic structure of UAl4 with point defects
dc.creator.none.fl_str_mv Kniznik, Laura
Alonso, Paula Regina
Gargano, Pablo Hugo
Rubiolo, Gerardo Hector
author Kniznik, Laura
author_facet Kniznik, Laura
Alonso, Paula Regina
Gargano, Pablo Hugo
Rubiolo, Gerardo Hector
author_role author
author2 Alonso, Paula Regina
Gargano, Pablo Hugo
Rubiolo, Gerardo Hector
author2_role author
author
author
dc.subject.none.fl_str_mv Actinide Materials And Compounds
Dft Calculations
Crystal Structure
Electronic Properties
topic Actinide Materials And Compounds
Dft Calculations
Crystal Structure
Electronic Properties
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv UAl4 ideal and defect structures were studied within the framework of the Density Functional Theory. The structural and magnetic ordering of UAl4 in paramagnetic, ferromagnetic, and antiferromagnetic states have been investigated, within the collinear and non-collinear spin approximation, using the GGA model, as embedded in the program package VASP. An antiferromagnetic ð011Þ layer structure with spins aligned to the [010] direction was found to be energetically preferred. The analysis of density of states and bonding charge density point out that the bonding mechanism consists primarily of band mixing between the U 5f and Al 3p states. Supercells were built from UAl4 unit cells with the established magnetic structure. For those supercells we calculated the energy of formation of vacancies and antisite defects taking into account the existence of three distinct aluminum sites. Point defect formation energies, local lattice relaxations, as well as the defect induced magnetic ordering and electronic density redistribution, are discussed. It is shown that antiferromagnetism is locally broken. Al antisites and U antisites in Al 4e Wyckoff positions are the constitutional point defects in Al-rich and U-rich oI20 UAl4, respectively. In this way we have presented here the first set of data which makes it possible to discuss and quantify the point defects concentrations in the experimental composition range for existence of this uranium aluminide.
Fil: Kniznik, Laura. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Comisión Nacional de Energía Atómica; Argentina
Fil: Alonso, Paula Regina. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Comisión Nacional de Energía Atómica; Argentina
Fil: Gargano, Pablo Hugo. Comisión Nacional de Energía Atómica; Argentina. Universidad Nacional de San Martín. Instituto Sabato; Argentina
Fil: Rubiolo, Gerardo Hector. Universidad Nacional de San Martín. Instituto Sabato; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina
description UAl4 ideal and defect structures were studied within the framework of the Density Functional Theory. The structural and magnetic ordering of UAl4 in paramagnetic, ferromagnetic, and antiferromagnetic states have been investigated, within the collinear and non-collinear spin approximation, using the GGA model, as embedded in the program package VASP. An antiferromagnetic ð011Þ layer structure with spins aligned to the [010] direction was found to be energetically preferred. The analysis of density of states and bonding charge density point out that the bonding mechanism consists primarily of band mixing between the U 5f and Al 3p states. Supercells were built from UAl4 unit cells with the established magnetic structure. For those supercells we calculated the energy of formation of vacancies and antisite defects taking into account the existence of three distinct aluminum sites. Point defect formation energies, local lattice relaxations, as well as the defect induced magnetic ordering and electronic density redistribution, are discussed. It is shown that antiferromagnetism is locally broken. Al antisites and U antisites in Al 4e Wyckoff positions are the constitutional point defects in Al-rich and U-rich oI20 UAl4, respectively. In this way we have presented here the first set of data which makes it possible to discuss and quantify the point defects concentrations in the experimental composition range for existence of this uranium aluminide.
publishDate 2015
dc.date.none.fl_str_mv 2015-08
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
http://purl.org/coar/resource_type/c_6501
info:ar-repo/semantics/articulo
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://hdl.handle.net/11336/41789
Kniznik, Laura; Alonso, Paula Regina; Gargano, Pablo Hugo; Rubiolo, Gerardo Hector; Energetics and electronic structure of UAl4 with point defects; Elsevier Science; Journal of Nuclear Materials; 466; 8-2015; 539-550
0022-3115
CONICET Digital
CONICET
url http://hdl.handle.net/11336/41789
identifier_str_mv Kniznik, Laura; Alonso, Paula Regina; Gargano, Pablo Hugo; Rubiolo, Gerardo Hector; Energetics and electronic structure of UAl4 with point defects; Elsevier Science; Journal of Nuclear Materials; 466; 8-2015; 539-550
0022-3115
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/url/https://www.sciencedirect.com/science/article/pii/S0022311515301859
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.jnucmat.2015.08.049
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
application/pdf
application/pdf
dc.publisher.none.fl_str_mv Elsevier Science
publisher.none.fl_str_mv Elsevier Science
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
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