Born--Oppenheimer dynamics using density-functional theory: Equilibrium and fragmentation of small sodium clusters

Journal Article · Tue Jan 01 04:00:00 EST 1991 · Journal of Chemical Physics; (USA)

DOI:https://doi.org/10.1063/1.460327· OSTI ID:6145668

Barnett, R N; Landman, U; Nitzan, A; Rajagopal, G ^[1]

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1. School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332 (US)

The properties of small neutral and positively charged sodium clusters and the fragmentation dynamics of Na{sup ++}{sub 4} are investigated using a simulation technique which combines classical molecular dynamics on the electronic Born--Oppenheimer ground-state potential surface with electronic structure calculations via the local spin-density functional method. Results for the optimal energies and structures of Na{sub {ital n}} and Na{sup +}{sub {ital n}} ({ital n}{le}4) are in quantitative agreement with previous studies and experimental data. Fission of Na{sup ++}{sub 4} on its ground state Born--Oppenheimer potential-energy surface, following sudden ionization of selected configurations of an Na{sup +}{sub 4} (or Na{sub 4}) cluster, whose vibrational energy content corresponds to 300 K, is found to occur on a picosecond time scale. The preferred fission channel is found to be Na{sup +}{sub 3}+Na{sup +}, with an interfragment relative translational kinetic energy of {similar to}2 eV, and a vibrationally excited Na{sup +}{sub 3}. The dynamics of the fragmentation process is analyzed.

• DOE Contract Number: FG05-86ER45234
• OSTI ID: 6145668
• Journal Information: Journal of Chemical Physics; (USA), Journal Name: Journal of Chemical Physics; (USA) Vol. 94:1; ISSN JCPSA; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
ALKALI METALS
BORN-OPPENHEIMER APPROXIMATION
CHARGED PARTICLES
ELECTRONIC STRUCTURE
ELEMENTS
EQUILIBRIUM
FRAGMENTATION
IONS
METALS
MOLECULAR IONS
SODIUM
SOLID CLUSTERS