title: The impact of electron correlations on the energetics and stability of silicon nanoclusters.
abstract: The first-principles prediction of stable nanocluster structure is often hampered by the existence of many isomer configurations with energies close to the ground state. This fact attaches additional importance to many-electron effects beyond density functional theory (DFT), because their contributions can change a subtle energy order of competitive structures. To analyze this problem, we consider, as an example, the energetics of silicon nanoclusters passivated by hydrogen Si10H2n (0 ≤ n ≤ 11), where passivation changes the structure from compact to loosely packed and branched. Our calculations performed with DFT, hybrid functionals, and Hartree-Fock methods, as well as by the GW approximation, confirm a considerable sensitivity of isomer energy ordering to many-electron effects.
authors.affiliation: P.N. Lebedev Physical Institute, Russian Academy of Sciences, Leninskii Prosp. 53, 119991 Moscow, Russia.
authors.forename: N L
authors.initials: NL
authors.lastname: Matsko
authors.affiliation: Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russia.
authors.forename: E V
authors.initials: EV
authors.lastname: Tikhonov
authors.affiliation: P.N. Lebedev Physical Institute, Russian Academy of Sciences, Leninskii Prosp. 53, 119991 Moscow, Russia.
authors.forename: V S
authors.initials: VS
authors.lastname: Baturin
authors.affiliation: P.N. Lebedev Physical Institute, Russian Academy of Sciences, Leninskii Prosp. 53, 119991 Moscow, Russia.
authors.forename: S V
authors.initials: SV
authors.lastname: Lepeshkin
authors.affiliation: Moscow Institute of Physics and Technology, Dolgoprudny, Moscow Region 141700, Russia.
authors.forename: Artem R
authors.initials: AR
authors.lastname: Oganov