A configurational study of helium clusters doped with He{sup ∗−} and He{sub 2}{sup ∗−}
Abstract
Helium clusters doped with electronically excited atomic and molecular helium anions He{sup ∗−} and He{sub 2}{sup ∗−} at T = 0.4 K are studied by means of path integral Monte Carlo calculations. Geometry and energetics of the systems with up to 32 solvating He atoms are characterised. The interactions between the anions and the neutral He atoms have been described by fitting previously reported ab initio points to analytical expressions. The He{sub N}–He{sup ∗−} clusters with N > 6 display a structure defined by a bipyramid which completely solvates the atomic anion, whereas the rest of surrounding He atoms form a dimple around that initial cage. On the contrary, the structures observed for the He{sub N}–He{sub 2}{sup ∗−} clusters clearly show the dopant located outside the helium droplet, thereby confirming the heliophobic character of He{sub 2}{sup ∗−}.
 Authors:
 Instituto de Física Fundamental, CSIC, Serrano 123, 28006 Madrid (Spain)
 Institute of Ion Physics, The University of Innsbruck, Technikerstr. 25, 6020 Innsbruck, Austriaand Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126 Pisa (Italy)
 Publication Date:
 OSTI Identifier:
 22415501
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 10; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ANIONS; DOPED MATERIALS; DROPLETS; HELIUM; MOLECULAR CLUSTERS; MOLECULAR IONS; MONTE CARLO METHOD; PATH INTEGRALS; SOLVATION; TEMPERATURE RANGE 00000013 K
Citation Formats
RodríguezCantano, Rocío, GonzálezLezana, Tomás, Email: t.gonzalez.lezana@csic.es, Villarreal, Pablo, and Gianturco, Franco A.. A configurational study of helium clusters doped with He{sup ∗−} and He{sub 2}{sup ∗−}. United States: N. p., 2015.
Web. doi:10.1063/1.4913958.
RodríguezCantano, Rocío, GonzálezLezana, Tomás, Email: t.gonzalez.lezana@csic.es, Villarreal, Pablo, & Gianturco, Franco A.. A configurational study of helium clusters doped with He{sup ∗−} and He{sub 2}{sup ∗−}. United States. doi:10.1063/1.4913958.
RodríguezCantano, Rocío, GonzálezLezana, Tomás, Email: t.gonzalez.lezana@csic.es, Villarreal, Pablo, and Gianturco, Franco A.. 2015.
"A configurational study of helium clusters doped with He{sup ∗−} and He{sub 2}{sup ∗−}". United States.
doi:10.1063/1.4913958.
@article{osti_22415501,
title = {A configurational study of helium clusters doped with He{sup ∗−} and He{sub 2}{sup ∗−}},
author = {RodríguezCantano, Rocío and GonzálezLezana, Tomás, Email: t.gonzalez.lezana@csic.es and Villarreal, Pablo and Gianturco, Franco A.},
abstractNote = {Helium clusters doped with electronically excited atomic and molecular helium anions He{sup ∗−} and He{sub 2}{sup ∗−} at T = 0.4 K are studied by means of path integral Monte Carlo calculations. Geometry and energetics of the systems with up to 32 solvating He atoms are characterised. The interactions between the anions and the neutral He atoms have been described by fitting previously reported ab initio points to analytical expressions. The He{sub N}–He{sup ∗−} clusters with N > 6 display a structure defined by a bipyramid which completely solvates the atomic anion, whereas the rest of surrounding He atoms form a dimple around that initial cage. On the contrary, the structures observed for the He{sub N}–He{sub 2}{sup ∗−} clusters clearly show the dopant located outside the helium droplet, thereby confirming the heliophobic character of He{sub 2}{sup ∗−}.},
doi = {10.1063/1.4913958},
journal = {Journal of Chemical Physics},
number = 10,
volume = 142,
place = {United States},
year = 2015,
month = 3
}

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