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Density Functional Theory study of the low-energy electronic structures and properties of small gold clusters : Zigzag gold nanoclusters

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 نشر من قبل Prashant Jain
 تاريخ النشر 2005
  مجال البحث فيزياء
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 تأليف Prashant K. Jain




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Gold clusters Aun of size n = 2 to 12 atoms were studied by the density-functional theory with an ab-initio pseudopotential and a generalized gradient approximation. Geometry optimizations starting from a number of initial candidate geometries were performed for each cluster size, so as to determine a number of possible low-energy isomers for each size. Along with the lowest-energy structures, metastable structures were obtained for many cluster sizes. Interestingly, a metastable planar zigzag arrangement of Au atoms was obtained for every cluster size n > = 5. The stable electronic structure, binding energy, relative stability and HOMO-LUMO gap for the lowest-energy isomer were calculated for each cluster size. Variation of the electronic properties with size is investigated in this paper and compared with experimental results and other calculations.

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