Interplay of electronic and geometry shell effects in properties of neutral and charged Sr clusters
Abstract
The optimized structure and electronic properties of neutral, singly, and doubly charged strontium clusters have been investigated using ab initio theoretical methods based on densityfunctional theory. We have systematically calculated the optimized geometries of neutral, singly, and doubly charged strontium clusters consisting of up to 14 atoms, average bonding distances, electronic shell closures, binding energies per atom, the gap between the highest occupied and the lowest unoccupied molecular orbitals, and spectra of the density of electronic states (DOS). It is demonstrated that the size evolution of structural and electronic properties of strontium clusters is governed by an interplay of the electronic and geometry shell closures. Influence of the electronic shell effects on structural rearrangements can lead to violation of the icosahedral growth motif of strontium clusters. It is shown that the excessive charge essentially affects the optimized geometry of strontium clusters. Ionization of small strontium clusters results in the alteration of the magic numbers. The strong dependence of the DOS spectra on details of ionic structure allows one to perform a reliable geometry identification of strontium clusters.
 Authors:
 Frankfurt Institute for Advanced Studies, Johann Wolfgang GoetheUniversity, MaxvonLaue Str. 1, 60438 Frankfurt am Main (Germany)
 (United Kingdom)
 Publication Date:
 OSTI Identifier:
 20982542
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. A; Journal Volume: 75; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevA.75.053201; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 74 ATOMIC AND MOLECULAR PHYSICS; ATOMIC CLUSTERS; ATOMS; BINDING ENERGY; DENSITY; DENSITY FUNCTIONAL METHOD; IONIZATION; MAGIC NUCLEI; SPECTRA; STRONTIUM
Citation Formats
Lyalin, Andrey, Imperial College of London, The Blackett Laboratory, Prince Consort Road, London SW7 2BW, Solov'yov, Ilia A., Solov'yov, Andrey V., and Greiner, Walter. Interplay of electronic and geometry shell effects in properties of neutral and charged Sr clusters. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVA.75.053201.
Lyalin, Andrey, Imperial College of London, The Blackett Laboratory, Prince Consort Road, London SW7 2BW, Solov'yov, Ilia A., Solov'yov, Andrey V., & Greiner, Walter. Interplay of electronic and geometry shell effects in properties of neutral and charged Sr clusters. United States. doi:10.1103/PHYSREVA.75.053201.
Lyalin, Andrey, Imperial College of London, The Blackett Laboratory, Prince Consort Road, London SW7 2BW, Solov'yov, Ilia A., Solov'yov, Andrey V., and Greiner, Walter. Tue .
"Interplay of electronic and geometry shell effects in properties of neutral and charged Sr clusters". United States.
doi:10.1103/PHYSREVA.75.053201.
@article{osti_20982542,
title = {Interplay of electronic and geometry shell effects in properties of neutral and charged Sr clusters},
author = {Lyalin, Andrey and Imperial College of London, The Blackett Laboratory, Prince Consort Road, London SW7 2BW and Solov'yov, Ilia A. and Solov'yov, Andrey V. and Greiner, Walter},
abstractNote = {The optimized structure and electronic properties of neutral, singly, and doubly charged strontium clusters have been investigated using ab initio theoretical methods based on densityfunctional theory. We have systematically calculated the optimized geometries of neutral, singly, and doubly charged strontium clusters consisting of up to 14 atoms, average bonding distances, electronic shell closures, binding energies per atom, the gap between the highest occupied and the lowest unoccupied molecular orbitals, and spectra of the density of electronic states (DOS). It is demonstrated that the size evolution of structural and electronic properties of strontium clusters is governed by an interplay of the electronic and geometry shell closures. Influence of the electronic shell effects on structural rearrangements can lead to violation of the icosahedral growth motif of strontium clusters. It is shown that the excessive charge essentially affects the optimized geometry of strontium clusters. Ionization of small strontium clusters results in the alteration of the magic numbers. The strong dependence of the DOS spectra on details of ionic structure allows one to perform a reliable geometry identification of strontium clusters.},
doi = {10.1103/PHYSREVA.75.053201},
journal = {Physical Review. A},
number = 5,
volume = 75,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}

Densityfunctional theory with generalized gradient approximation for the exchangecorrelation potential has been used to calculate the global equilibrium geometries and electronic structure of neutral, cationic, and anionic aluminum clusters containing up to 15 atoms. The total energies of these clusters are then used to study the evolution of their binding energy, relative stability, fragmentation channels, ionization potential, and vertical and adiabatic electron affinities as a function of size. The geometries are found to undergo a structural change from two dimensional to three dimensional when the cluster contains 6 atoms. An interior atom emerges only when clusters contain 11 or moremore »

Structural and electronic properties of neutral and charged silicalike clusters
The electronic and structural properties of neutral and charged Si{sub n}O{sub n} clusters, with n=3, 4, and 5, and related clusters, are examined using the higherorder finitedifference pseudopotential method. The groundstate structures for these clusters are determined via a simulated annealing procedure. The photoemission spectra for negatively charged clusters Si{sub n}O{sub n}{sup {minus}} are simulated at finite temperatures using quantum forces coupled with Langevin dynamics. The simulated spectra are in good agreement with measured spectra. In contrast to previously predicted structures, we find the lowestenergy structures for Si{sub 4}O{sub 4} and Si{sub 5}O{sub 5} correspond to nonplanar rings. {copyright} {italmore » 
Firstprinciples investigation of the dissociation and coupling of methane on small copper clusters: Interplay of collision dynamics and geometric and electronic effects
Small metal clusters exhibit unique size and morphology dependent catalytic activity. The search for alternate minimum energy pathways and catalysts to transform methane to more useful chemicals and carbon nanomaterials led us to investigate collision induced dissociation of methane on small Cu clusters. We report here for the first time, the free energy barriers for the collision induced activation, dissociation, and coupling of methane on small Cu clusters (Cu{sub n} where n = 2–12) using ab initio molecular dynamics and metadynamics simulations. The collision induced activation of the stretching and bending vibrations of methane significantly reduces the free energy barriermore » 
Theoretical and Electrochemical Study of the QuinoneBenzoic Acid Adduct Linked by Hydrogen Bonds DFT Study of Electronic Structure and Geometry of Neutral and Anionic Silver Clusters
A comparative analysis of bond lengths vertical detachment energies (VDE), excitation energies of neutral clusters with geometry of anions and vertical ionization potentials of neutral clusters calculated within density functional theory (DFT) using different functionals with both effective core potential (ECP) and allelectron basis sets for silver clusters Ag n, have been carried out. DFT methods provide a good agreement between calculated and experimental data of some characteristics. The accurate prediction of all characteristics simultaneously can be achieved with allelectron DZVP basis set only. A new functional has been developed. It provides results close to experimental data using the moderatemore » 
Atomic and electronic structures of neutral and charged boron and boronrich clusters
{ital Ab initio} molecular orbital theory based on both density functional formalism and quantum chemical methods has been used to calculate the equilibrium geometries, binding energies, ionization potentials, fragmentation patterns, and electronic structures of neutral and charged boron clusters containing up to six atoms. Calculations have also been performed on restricted geometries for B{sub n}X (n=1,5,12; X=Be, B, C) and B{sub 20} clusters to see if clusters can be designed so as to increase their stability. Energetics of doubly charged B{sub n}{sup ++} clusters have also been studied to find the critical size for Coulomb explosion. The results are comparedmore »