Zakharov P.V., Eremin A.M., Manakov N.A., Starostenkov M.D., Markidonov A.V.
BEHAVIOR OF THE QUASI-BREATHER MODE IN PT₃AL CRYSTAL WITH THE POINT DEFECTS ^{[№ 9 ' 2015]}
Nowadays the localized oscillations of the atoms or separate atomic groups are being studied in the perfect chips what makes the usage of the acquired results more difficult when studying the real crystals with the deffects. In this researсh by the method of molecular dynamics we study influence of the point defects on the quasi-breather mode behavior in stoichiometry crystal A3B using Pt₃Al as an example. As point defects there are divacancies, trivacancies Pt in the crystal of Pt₃Al as well as interstitial atoms of Al that are placed into the tetrahedral vacuums. The considered model is a bulk stoichiometry crystal A₃B, where the atoms interact through Morse pair potential. It was found that point defects within Pt₃Al alloy substantially influence on the quasi-breather mode in the case of their close arrangement. The exposure is in the high-amplitude localized oscillations destruction with the further energy dispersion through the crystal. But it's worth to remark that while high-amplitude oscillations degradation dispersion predominantly takes place into Al sublattice where the energy stays localized because of the forbidden band availability in the phonon spectrum of Pt₃Al crystal during the long period of time. Besides it's established that there is a quasi-breather mode extended stability region near Pt divacancy and trivacancy. In the event of the observing at the point defect in the form of the interstitial Al atom, that is implantated into the tetrahedral vacuum such region does not exist. The acquired results should be counted while investigating the features and qualities of the real stoichiometry crystals А₃В.