ГеохимияГеохимия0016-7525The Russian Academy of Sciences1617610.31857/S0016-7525649936-947Research ArticleIron and its compounds in the earth’s core: new data and ideasPushcharovskyD. Yu.<p>Faculty of Geology</p>dean@geol.msu.ruLomonosov Moscow State University200920196499369472009201920092019Copyright © 2019, Russian Academy of Sciences2019<p>Iron-the most abundant chemical element in the Earths core, which it is more than 85% by weight. The remaining ~15% weight of the nucleus is accounted for Ni, and some lighter elements: Si, C, S, O, and H. New data of the transformations of iron and its compounds under the influence of high temperature and pressure, which modeling conditions in the Earths core, are analyzed. Structural types of mineralogically possible polymorphic modifications of iron and its compounds in deep geospheres in the Earths core are considered. New data about changes in the electronic structure of iron atoms at high pressure are presented. Scientific ideas were expanded and new ideas were put forward about the forms of concentration of chemical elements at ultra-high temperature and pressure. It is concluded that modern views on the specific features and properties of the Earths mantle and core are based not only on the results of geological and geophysical methods, but are clarified using micro-mineralogical and crystallographic approaches.</p>Earth corepolymorphic modifications of iron and its compoundsядро Землиполиморфные модификации железа и его соединений[Бажанова З.Г., Оганов А.Р., Джанола О. (2012) Системы Fe-C и Fe-H при давлениях внутреннего ядра Земли. УФН 182, 521-530.][Бажанова З.Г., Ройзен В.В., Оганов А.Р. (2017) Поведение системы Fe-S при высоких давлениях и состав ядра Земли. УФН 187, 1105-1113.][Литасов К.Д., Шацкий А.Ф. (2016 а) Состав и строение ядра Земли. Новосибирск: Изд-во СО РАН, 304 с.][Литасов К.Д., Шацкий А.Ф. (2016б) Современные представления о составе ядра Земли. 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