Computational study of the stable atomic trapping sites in Ar lattice
Georgiy K. Ozerov1, Dmitry S. Bezrukov1,2, and Alexei A. Buchachenko1
1Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, Building 3, Moscow 143026, Russia
2Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow 119991, Russia
Received October 24, 2018
Stable atomic trapping sites in the Lennard-Jones face-centered cubic Ar crystals are investigated by means of the global optimization strategy and convex hull concept for thermodynamic stability. Five generic site types are found in full accord with crystallographic intuition: interstitial within tetrahedral and octahedral hollows and substitutions, single, tetra- and hexavacancy. Their identities are established by radial distribution function analysis. Stability regions of these sites are mapped into the space of Lennard-Jones parameters of the guest–host interatomic interaction. Predictions made for the number and types of the stable sites for selected atoms (H, Mn, Na, Yb, Eu, Ba) are found to be in line with the results of more sophisticated models and matrix isolation spectroscopy experiments.
Key words: rare gas solids, trapping site, guest–host interaction.