Crystal structure and magnetic properties of lepidocrocite upon thermal transformation to hematite


Тип публикации: статья из журнала

Год издания: 1974

Идентификатор DOI: 10.1007/BF00893038

Аннотация: Synthesized lepidocrocite (?-FeOOH) has a unit cell of the rhombic system (a = 3.86 A, b = 12.49, and c = 3.36). In the 230-250°C region the structure of lepidocrocite is reconstructed to cubic (a = 8.331 ± 0.003 A) maghemite (?-Fe2O3), which at 375°C is transformed completely to hematite (?-Fe2O3) with a hexagonal structure which Показать полностьюbecomes more perfect with further heating (a = 5.0330 ± 0.002 A, c = 13.748 ± 0.002 A). Lepidocrocite occurs in a paramagnetic state. The intermediate substance of its thermal transformation, maghemite, as a consequence of high dispersion, is characterized by superparamagnetic properties and the end product, hematite, owing to the presence of Dzialoshinski's moment, has weak ferromagnetism. © 1974 Consultants Bureau.

Ссылки на полный текст


Журнал: Soviet Physics Journal

Выпуск журнала: Vol. 15, Is. 5

Номера страниц: 698-702


Вхождение в базы данных