title: Many-body effects on the structures and stability of Ba²⁺Xe(n) (n = 1-39, 54) clusters.
abstract: The structures and relative stabilities of mixed Ba(2+)Xe(n) (n = 1-39, 54) clusters have been theoretically studied using basin-hopping global optimization. Analytical potential energy surfaces were constructed from ab initio or experimental data, assuming either purely additive interactions or including many-body polarization effects and the mutual contribution of self-consistent induced dipoles. For both models the stable structures are characterized by the barium cation being coated by a shell of xenon atoms, as expected from simple energetic arguments. Icosahedral packing is dominantly found, the exceptional stability of the icosahedral motif at n = 12 being further manifested at the size n = 32 where the basic icosahedron is surrounded by a dodecahedral cage, and at n = 54 where the transition to multilayer Mackay icosahedra has occurred. Interactions between induced dipoles generally tend to decrease the Xe-Xe binding, leading to different solvation patterns at small sizes but also favoring polyicosahedral growth. Besides attenuating relative energetic stability, many-body effects affect the structures by expanding the clusters by a few percents and allowing them to deform more.
authors.affiliation: Laboratoire de Physique Quantique, Faculté des Sciences de Monastir, Université de Monastir, Avenue de l'Environnement, 5019 Monastir, Tunisia.
authors.forename: Kawther
authors.initials: K
authors.lastname: Abdessalem
authors.affiliation: Laboratoire de Physique Quantique, Faculté des Sciences de Monastir, Université de Monastir, Avenue de l'Environnement, 5019 Monastir, Tunisia.
authors.forename: Héla
authors.initials: H
authors.lastname: Habli
authors.affiliation: Laboratoire de Physique Quantique, Faculté des Sciences de Monastir, Université de Monastir, Avenue de l'Environnement, 5019 Monastir, Tunisia.
authors.forename: Houcine
authors.initials: H
authors.lastname: Ghalla
authors.affiliation: Physics Department, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia.
authors.forename: Saud Jamil
authors.initials: SJ
authors.lastname: Yaghmour
authors.affiliation: University of Grenoble Alpes, LIPHY, F-38000 Grenoble, France and CNRS, LIPHY, F-38000 Grenoble, France.
authors.forename: Florent
authors.initials: F
authors.lastname: Calvo
authors.affiliation: Laboratoire de Physique Quantique, Faculté des Sciences de Monastir, Université de Monastir, Avenue de l'Environnement, 5019 Monastir, Tunisia.
authors.forename: Brahim
authors.initials: B
authors.lastname: Oujia