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Information × Registration Number 0220U100082, 0119U101878 , R & D reports Title Detection of new properties of disordered materials under extreme conditions: Ab initio simulation approach. popup.stage_title Head Bryk Taras M., Доктор фізико-математичних наук Registration Date 09-01-2020 Organization Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine popup.description2  The project “Revealing new properties of disordered materials at extremal conditions: Ab initio simulation approach” is aimed at the search for new properties of materials at high temperatures and pressures. Long-time ab initio simulations were performed for molten C, B, Si, Al, GaSb and Tl-Te. The obtained results for dynamic properties of molten С at temperature 5500K are very new. For the first time there were obtained in ab initio simulations two clear contributions to the longitudinal current spectral function, one of which comes from non-hydrodynamic collective process and is not observed at ambient conditions. Additional simulations, performed for molten B and Si, point out, that this phenomenon is caused by specific features of the medium-range order. A comparison of spectra of longitudinal and transverse modes makes evidence that the low-frequency contribution comes from the transverse modes. Important contributions to understanding the structure and dynamics of complex many-component systems at extreme conditions of high temperatures and pressures can be the ab initio simulations performed for binary melts GaSb and for several compositions of Tl-Te. Rapid changes of atomistic structure at elevating temperature and composition change were observed. Product Description popup.authors Hordijchuk Volodymyr V. Demchuk Taras V. Trokhymchuk Andrii D. popup.nrat_date 2020-04-02 Close