Density functional theory of the structure of magnesium-doped helium nanodroplets

We have studied the structure of 4 He droplets doped with magnesium atoms using density functional theory. We have found that the solvation properties of this system strongly depend on the size of the 4 He droplet. For small drops, Mg resides in a deep surface state, whereas for large-size drops it...

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Autores: Hernando, Alberto, Barranco Gómez, Manuel, Mayol Sánchez, Ricardo, Pi Pericay, Martí, Ancilotto, Francesco
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2008
País:España
Institución:Universidad de Barcelona
Repositorio:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/10588
Acceso en línea:https://hdl.handle.net/2445/10588
Access Level:acceso abierto
Palabra clave:Teoria del funcional de densitat
Dinàmica de fluids
Heli
Magnesium
Espectres d'absorció
Density functional theory
Fluid dynamics
Helium
Absorption spectra
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spelling Density functional theory of the structure of magnesium-doped helium nanodropletsHernando, AlbertoBarranco Gómez, ManuelMayol Sánchez, RicardoPi Pericay, MartíAncilotto, FrancescoTeoria del funcional de densitatDinàmica de fluidsHeliMagnesiumEspectres d'absorcióDensity functional theoryFluid dynamicsHeliumMagnesiumAbsorption spectraWe have studied the structure of 4 He droplets doped with magnesium atoms using density functional theory. We have found that the solvation properties of this system strongly depend on the size of the 4 He droplet. For small drops, Mg resides in a deep surface state, whereas for large-size drops it is fully solvated but radially delocalized in their interior. We have studied the 3s3p1 P1←3s21 S0 transition of the dopant, and have compared our results with experimental data from laser-induced fluorescence LIF. Line-broadening effects due to the coupling of dynamical deformations of the surrounding helium with the dipole excitation of the impurity are explicitly taken into account. We show that the Mg radial delocalization inside large droplets may help reconcile the apparently contradictory solvation properties of magnesium as provided by LIF and electronimpact ionization experiments. The structure of 4 He drops doped with two magnesium atoms is also studied and used to interpret the results of resonant two-photon-ionization R2PI and LIF experiments. We have found that the two solvated Mg atoms do not easily merge into a dimer, but rather form a weakly bound state due to the presence of an energy barrier caused by the helium environment that keeps them some 9.5 Å apart, preventing the formation of the Mg2 cluster. From this observation, we suggest that Mg atoms in 4 He drops may form, under suitable conditions, a soft “foamlike” aggregate rather than coalesce into a compact metallic cluster. Our findings are in qualitative agreement with recent R2PI experimental evidence. We predict that, contrarily, Mg atoms adsorbed in 3 He droplets do not form such metastable aggregates.The American Physical Society2008info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionapplication/pdfhttps://hdl.handle.net/2445/10588Articles publicats en revistes (Física Quàntica i Astrofísica)reponame:Dipòsit Digital de la UBinstname:Universidad de BarcelonaInglésReproducció digital del document publicat en format paper, proporcionada per PROLA i http://dx.doi.org/10.1103/PhysRevB.78.184515Physical Review B, 2008, vol. 78, núm. 18, p. 184515-184515-19http://dx.doi.org/10.1103/PhysRevB.78.184515(c) The American Physical Society, 2008info:eu-repo/semantics/openAccessoai:diposit.ub.edu:2445/105882026-05-27T06:46:51Z
dc.title.none.fl_str_mv Density functional theory of the structure of magnesium-doped helium nanodroplets
title Density functional theory of the structure of magnesium-doped helium nanodroplets
spellingShingle Density functional theory of the structure of magnesium-doped helium nanodroplets
Hernando, Alberto
Teoria del funcional de densitat
Dinàmica de fluids
Heli
Magnesium
Espectres d'absorció
Density functional theory
Fluid dynamics
Helium
Magnesium
Absorption spectra
title_short Density functional theory of the structure of magnesium-doped helium nanodroplets
title_full Density functional theory of the structure of magnesium-doped helium nanodroplets
title_fullStr Density functional theory of the structure of magnesium-doped helium nanodroplets
title_full_unstemmed Density functional theory of the structure of magnesium-doped helium nanodroplets
title_sort Density functional theory of the structure of magnesium-doped helium nanodroplets
dc.creator.none.fl_str_mv Hernando, Alberto
Barranco Gómez, Manuel
Mayol Sánchez, Ricardo
Pi Pericay, Martí
Ancilotto, Francesco
author Hernando, Alberto
author_facet Hernando, Alberto
Barranco Gómez, Manuel
Mayol Sánchez, Ricardo
Pi Pericay, Martí
Ancilotto, Francesco
author_role author
author2 Barranco Gómez, Manuel
Mayol Sánchez, Ricardo
Pi Pericay, Martí
Ancilotto, Francesco
author2_role author
author
author
author
dc.subject.none.fl_str_mv Teoria del funcional de densitat
Dinàmica de fluids
Heli
Magnesium
Espectres d'absorció
Density functional theory
Fluid dynamics
Helium
Magnesium
Absorption spectra
topic Teoria del funcional de densitat
Dinàmica de fluids
Heli
Magnesium
Espectres d'absorció
Density functional theory
Fluid dynamics
Helium
Magnesium
Absorption spectra
description We have studied the structure of 4 He droplets doped with magnesium atoms using density functional theory. We have found that the solvation properties of this system strongly depend on the size of the 4 He droplet. For small drops, Mg resides in a deep surface state, whereas for large-size drops it is fully solvated but radially delocalized in their interior. We have studied the 3s3p1 P1←3s21 S0 transition of the dopant, and have compared our results with experimental data from laser-induced fluorescence LIF. Line-broadening effects due to the coupling of dynamical deformations of the surrounding helium with the dipole excitation of the impurity are explicitly taken into account. We show that the Mg radial delocalization inside large droplets may help reconcile the apparently contradictory solvation properties of magnesium as provided by LIF and electronimpact ionization experiments. The structure of 4 He drops doped with two magnesium atoms is also studied and used to interpret the results of resonant two-photon-ionization R2PI and LIF experiments. We have found that the two solvated Mg atoms do not easily merge into a dimer, but rather form a weakly bound state due to the presence of an energy barrier caused by the helium environment that keeps them some 9.5 Å apart, preventing the formation of the Mg2 cluster. From this observation, we suggest that Mg atoms in 4 He drops may form, under suitable conditions, a soft “foamlike” aggregate rather than coalesce into a compact metallic cluster. Our findings are in qualitative agreement with recent R2PI experimental evidence. We predict that, contrarily, Mg atoms adsorbed in 3 He droplets do not form such metastable aggregates.
publishDate 2008
dc.date.none.fl_str_mv 2008
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
format article
status_str publishedVersion
dc.identifier.none.fl_str_mv https://hdl.handle.net/2445/10588
url https://hdl.handle.net/2445/10588
dc.language.none.fl_str_mv Inglés
language_invalid_str_mv Inglés
dc.relation.none.fl_str_mv Reproducció digital del document publicat en format paper, proporcionada per PROLA i http://dx.doi.org/10.1103/PhysRevB.78.184515
Physical Review B, 2008, vol. 78, núm. 18, p. 184515-184515-19
http://dx.doi.org/10.1103/PhysRevB.78.184515
dc.rights.none.fl_str_mv (c) The American Physical Society, 2008
info:eu-repo/semantics/openAccess
rights_invalid_str_mv (c) The American Physical Society, 2008
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv The American Physical Society
publisher.none.fl_str_mv The American Physical Society
dc.source.none.fl_str_mv Articles publicats en revistes (Física Quàntica i Astrofísica)
reponame:Dipòsit Digital de la UB
instname:Universidad de Barcelona
instname_str Universidad de Barcelona
reponame_str Dipòsit Digital de la UB
collection Dipòsit Digital de la UB
repository.name.fl_str_mv
repository.mail.fl_str_mv
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