Инд. авторы:	Sagatova D.N., Gavryushkin P.N., Sagatov N.E., Medrish I.V., Litasov K.D.
Заглавие:	Phase Diagrams of Iron Hydrides at Pressures of 100-400 GPa and Temperatures of 0-5000 K
Библ. ссылка:	Sagatova D.N., Gavryushkin P.N., Sagatov N.E., Medrish I.V., Litasov K.D. Phase Diagrams of Iron Hydrides at Pressures of 100-400 GPa and Temperatures of 0-5000 K // Journal of Experimental and Theoretical Physics Letters (JETP Letters). - 2020. - Vol.111. - Iss. 3. - P.145-150. - ISSN 0021-3640. - EISSN 1090-6487.
Внешние системы:	DOI: 10.1134/S0021364020030108; WoS: 000526455500004;
Реферат:	eng: The stability of Fe4H, Fe2H, FeH, Fe3H5, FeH2, FeH3, FeH4, Fe3H13, FeH5, and FeH6 iron hydrides at temperatures of 0-5000 K and pressures of 100-400 GPa has been analyzed for the first time in the density functional theory using the lattice dynamics method in the quasiharmonic approximation, and the corresponding PT phase diagrams have been obtained. It has been found that heating expands a set of stable stoichiometric compounds, so that a number of structures metastable at room temperature are stabilized at temperatures above 1000 K. The topological analysis of structures of iron hydrides indicates that most of them belong to rare or unique topological types. An increase in the amount of hydrogen in a structure is accompanied by the reduction of the length of an H-H bond, which results in the formation of dumbbell-like hydrogen molecules H-2 in FeHx structures with x > 6. However, these structures are thermodynamically unstable and decay into a mixture of FeH6 and solid H.
Ключевые слова:	LANTHANUM; STABILITY; SUPERCONDUCTIVITY; HYDROGEN; CRYSTAL-STRUCTURES; ELECTRONIC-PROPERTIES; TOTAL-ENERGY CALCULATIONS; EARTHS CORE;
Издано:	2020
Физ. характеристика:	с.145-150