The DFT-genetic algorithm approach for global optimization of subnanometer bimetallic clusters

Over the past two decades, there have been significant developments of sophisticated search algorithms, in particular, genetic algorithms (GAs). GAs have been used to predict the structures (and hence the physical and chemical properties) of mixed-metal “nanoalloy” clusters, with an emphasis on subnanometer clusters, via the coupling of the GA with electronic structure calculations, particularly density functional theory. In collaboration with a number of theoreticians and experimentalists, we have employed different computational approaches and high-performance computing architectures to develop our in-house GA codes and used them to complement experimental studies. In this chapter, we review the basics of GAs, as applied to clusters, and historical developments of the GA programs to allow the exploration of cluster energy surfaces and the search for global minima, at different levels of theory. A range of example applications are introduced, included optical, electronic, and catalytic applications of free and surface-supported pure metal clusters and nanoalloys. Finally, we discuss some possible future developments.