RT info:eu-repo/semantics/article
T1 Correlation between the latent heats and cohesive energies of metal clusters
A1 Starace, Anne K.
A1 Neal, Colleen M.
A1 Cao, Baopeng
A1 Jarrold, Martin F.
A1 Aguado Rodríguez, Andrés
A1 López Rodríguez, José Manuel
K1 Materia-Estructura
AB Dissociation energies have been determined for Al_n^+ clusters (n = 25–83) using a new experimental approach that takes into account the latent heat of melting. According to the arguments presented here, the cohesive energies of the solidlike clusters are made up of contributions from the dissociation energies of the liquidlike clusters and the latent heats for melting. The size-dependent variations in the measured dissociation energies of the liquidlike clusters are small and the variations in the cohesive energies of solidlike clusters result almost entirely from variations in the latent heats for melting. To compare with the measured cohesive energies, density-functional theory has been used to search for the global minimum energy structures. Four groups of low energy structures were found: Distorted decahedral fragments, fcc fragments, fcc fragments with stacking faults, and “disordered.” For most cluster sizes, the measured and calculated cohesive energies are strongly correlated. The calculations show that the variations in the cohesive energies (and the latent heats) result from a combination of geometric and electronic shell effects. For some clusters an electronic shell closing is responsible for the enhanced cohesive energy and latent heat (e.g., n = 37), while for others (e.g., n = 44) a structural shell closing is the cause.
PB American Institute of Physics
YR 2008
FD 2008
LK http://uvadoc.uva.es/handle/10324/2521
UL http://uvadoc.uva.es/handle/10324/2521
LA eng
NO Journal of Chemical Physics, v. 129, n. 14, (2008) p. 1-10
NO Producción Científica
DS UVaDOC
RD 24-nov-2024