Theoretical Study of Structural Symmetry in Ternary Clusters

Abstract

The geometrical symmetry presents an intriguing theoretical problem in many kinds of clusters. The diversity of geometrical structures is associated with cluster sizes, different model functions and potential parameters, and ternary clusters are investigated to study the relationship between geometrical symmetry and homotopic symmetry. Ternary Lennard-Jones model potential is studied with different parameters, and the putative global minimum structures of A 13 B 30 C 12 clusters are optimized using an adaptive immune optimization algorithm. The results show that there mainly exist five geometrical symmetry structures, i.e., Mackay icosahedral, fivefold partial Mackay icosahedral, sixfold pancake, partial double Mackay icosahedral, and amorphous structures. Furthermore, the number of bonds is used to distinguish the geometrical symmetry. The importance of geometrical symmetry and homotopic symmetry determined by potential parameters is discussed. It was found that in the optimization it is more important to generate geometrical symmetry than to optimize homotopic symmetry.

Theoretical investigation of the structures of unsupported 38-atom CuPt clusters

“…The procedure outlined in this investigation can be implemented for tuning empirical potential parameters to reproduce experimental observations of nanoalloy structures. This approach can be applied to a large number of binary clusters and nanoalloys using the Gupta potential, or other empirical potentials that model non-metal interactions, for example the Lennard-Jones potential [52]. The structures predicted using empirical potentials might be utilized as input configurations in studies with a higher level of theory, e. g., in the range of nanoparticle sizes ( 2 nm) where it is too computationally expensive to perform global searches at the DFT level, but where DFT local optimization and, calculation of physicochemical properties can be performed on ground-state and low-lying isomer structures, for example to explain the differences in catalytic performance found for particular CuPt nanoalloys [53].…”

The composition effect on the structural and thermodynamic properties of Cu–Ag–Au ternary nanoalloys: a study via molecular dynamics approach

“…Therefore, using this Mackay-icosahedron formula, we obtain a total number of 5083 atoms for a shell of k = 12. It is opportune to highlight that one of the five geometrical symmetry structures of the ternary clusters is the Mackay icosahedral [40,41]. Furthermore, we have considered the following expression for the composition:…”