hcp metal nanoclusters with hexagonal A-A bilayer stacking stabilized by enhanced covalent bonding.
PHYS REV B
First-principles total energy calculations within density functional theory have been performed to study the geometric and electronic structures of Run nanoclusters of varying size n (14 <= n <= 42). Strikingly, for the size range of n = 14 to 38, the clusters always prefer a hexagonal bilayer structure with A-A stacking, rather than some of the more closely packed forms, or bilayer with A-B stacking. Such an intriguing "molecular double-wheel" form is stabilized by substantially enhanced interlayer covalent bonding associated with strong s-d hybridization. Similar A-A stacking is also observed in the ground states or low-lying isomers of the clusters composed of other hcp elements, such as Os, Tc, Re, and Co. Note that these "molecular double-wheels" show enhanced chemical activity toward H2O splitting relative to their bulk counterpart, implying its potential applications as nanocatalysts.
|Title:||hcp metal nanoclusters with hexagonal A-A bilayer stacking stabilized by enhanced covalent bonding|
|Keywords:||TOTAL-ENERGY CALCULATIONS, AUGMENTED-WAVE METHOD, ELASTIC BAND METHOD, SADDLE-POINTS, BASIS-SET, ADSORPTION, SURFACES, CLUSTERS, WATER, DISSOCIATION|
|UCL classification:||UCL > School of BEAMS > Faculty of Maths and Physical Sciences
UCL > School of BEAMS > Faculty of Maths and Physical Sciences > Chemistry
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