I.S. Zamulin - Ph.D. (Phys.-Math.), Research Scientist, Khakas State University, Abakan. E-mail: zamulin_ivan@mail.ru М.D. Starostenkov - Dr.Sc. (Phys.-Math.), Professor, Polzunov Altai State Technical University (AltSTU), Barnaul. E-mail: genphys@mail.ru

With the use of molecular dynamics methods there were simulated structural transformations in small Pt, Pd, and Rh clusters under thermal effect. The modelling of melting and crystallization processes was performed within the framework of canonic ensemble based upon interaction with Noze thermostat. It was discovered that Pt and Pd small nanoclusters have normally face-centred lattice as a stable structure, while Rh has the icosahedral one. As to Pt and Pd, the «magic» numbers for face-centred structure hold true always, at least for cluster diameter down to 2 nm. In Rh clusters with the diameter more than 1,7 nm the face-centred structure transformed to the icosahedral one. It can be explained by the height of the energy barrier: for Rh it is much lower than for Pt and Pd.

 

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