Der Pharma Chemica
Journal for Medicinal Chemistry, Pharmaceutical Chemistry, Pharmaceutical Sciences and Computational Chemistry


Geometries and Electronic Structures by DFT Simulated Annealing Study of Some Noble Metal Small Size Clusters

Author(s): Benkrima Yamina, Ouahab Abdelouahab

The minimum energy geometries and the electronic structure for noble metals clusters Agn, Aun, Ptn and Cun, with number of atoms n varying from 3 to 10 atoms are obtained employin density functional theory (DFT) with generalized gradient approximation (GGA) performed in the SIESTA method. New lowest energy structures not reported previously are obtained. The lowest energy structures for (n ≤ 5) clusters are planar where the stability showed that the highest value in binding energy is present in platinum. The calculated second–order differences in energies, and the highest occupied orbital-lowest unoccupied orbital (HOMO-LUMO) energy gap, the density of state (DOS) shows peculiar odd-even oscillation behaviours, showing that Ag4,6,8,10, Au4,6,8,10, Cu4,6,8,10 and Pt3,7,9 clusters remain in highly stable in comparison with their neighboring clusters. (VIP) Vertical ionization potential is discussed then compared with other studies.