A theoretical study of the lowest-energy PtPd co-doped silicon clusters: Chirality and fluxional transformation

The lowest-energy structures of PtPdSiqn (n=1-7; q=0,±1) clusters are searched based on the PSO algorithm implemented in the CALYPSO code and the first-principle DFT-D computations implemented in DMol3 code. Interestingly, the chirality has been found for the lowest-energy structures of the neutral and charged PtPdSi4, neutral and anionic PtPdSi5, and cationic PtPdSi7 clusters. The first principles molecular dynamics (MD) simulations show that the fluxional transformation between the chiral configurations for neutral PtPdSi4 cluster can take place at 400 K, which is also confirmed by the rather small transformation barrier. The equivalent atoms involved in the bond breaking and formation, as well as the other atoms (modulator), may facilitate the dynamical behavior. The current finding is thus beyond imagination. It is noticeable that the current study provides a potential way to create interesting cluster with chirality and transformation, based on silicon.