RT info:eu-repo/semantics/article
T1 Orbital-free molecular dynamics simulations of melting in Na_8 and Na_20 : Melting in steps
A1 Aguado Rodríguez, Andrés
A1 López Rodríguez, José Manuel
A1 Alonso Martín, Julio Alfonso
A1 Stott, Malcolm J.
K1 Física nuclear
K1 Dinámica molecular
AB The melting-like transitions of Na_8 and Na_20 are investigated by ab initio constant energy molecular dynamics simulations using a variant of the Car–Parrinello method which employs an explicit electronic kinetic energy functional of the density, thus avoiding the use of one-particle orbitals. Several melting indicators are evaluated in order to determine the nature of the various transitions, and are compared with other simulations. Both Na8 and Na_20 melt over a wide temperature range. For Na_8, a transition is observed to begin at ∼110 K, between a rigid phase and a phase involving isomerizations among the different permutational isomers of the ground state structure. The “liquid” phase is completely established at ∼220 K. For Na_20, two transitions are observed: the first, at ∼110 K, is associated with isomerization transitions among those permutational isomers of the ground state structure which are obtained by interchanging the positions of the surface-like atoms; the second, at ∼160 K, involves a structural transition from the ground state isomer to a new set of isomers with the surface molten. The cluster is completely liquid at ∼220 K.
PB American Institute of Physics
YR 1999
FD 1999
LK http://uvadoc.uva.es/handle/10324/2512
UL http://uvadoc.uva.es/handle/10324/2512
LA eng
NO Journal of Chemical Physics v. 111, n. 13, (1999) p. 6026-6035
NO Producción Científica
DS UVaDOC
RD 24-nov-2024