On the structural stability of mono- and binary metallic nanocages

Abstract

This work is devoted to the problem of thermal stability of mono- and binary metal nanocages consisting of gold and silver atoms. The number of atoms in the studied nanocages was 1744, 2150, 2470 and 3370 atoms. The characteristic size (outer diameter) of nanocages is from 4,4 to 5,1 nm. Interatomic interaction was described by the tight-binding potential. Analysis of the caloric dependences of the specific potential part of the internal energy made it possible to identify the temperature regions of «healing» of cavities (pores) on the faces and in the internal regions (cores) of nanocages. An example of the structural collapse of a nanocage is described in detail, as a result of which crystalline and quasicrystalline phases are identified in the nanoparticle core for a temperature corresponding to melting for the chosen size. Segregation in a binary Au-Ag nanocage before and after its collapse was also studied.

Keywords

• atomistic simulation
• tight binding potential
• metallic nanocages
• porеs
• thermal effects
• stability/instability
• structure formation