Theoretical investigation of the stability of A55-nBn nanoalloys (A, B = Al, Cu, Zn, Ag).

Nanoalloys have been investigated for a wide range of applications, however, our atomistic understanding of the physical-chemistry properties is still far from complete as quantum-size effects play an important role for particles with about 1 nm diameter. In this work, we employed density functional theory calculations to investigate the structural, energetic and electronic properties of 55-atom A 55- n B n nanoalloys, where A , B = Al, Cu, Zn, and Ag. For structure generation, we combined clustering algorithm techniques with design principles, which yields a wide range of conformations. From the analyses of the excess energy results, we found that the CuAl, CuAg, CuZn, and AlAg systems are the most energetically favorable, in particular, the Al 42 Cu 13 and Al 42 Ag 13 compositions (onion-like and core–shell structures, respectively). Through Spearman's correlation analysis, we found that the structural properties (number of under coordinated atoms, effective coordination number, average bond lengths, and chemical order parameter) are the most important descriptors correlated with the energy stability of the nanoalloys (excess energy). Several properties such as the particle volume, binding energy, and average bond length show a linear dependence as a function of composition. [ABSTRACT FROM AUTHOR]