G 96 Gusev, A. I. A sequence of transformations related to the formation of M3X2-type superstructures / A. I. Gusev // Journal of Experimental and Theoretical Physics. - 2015. - Vol. 120, № 1. - P91-96 Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): M3X2 -- КАРБИД ВАНАДИЯ -- НЕСТЕХИОМЕТРИЯ -- НАНОСТРУКТУРА Аннотация: A symmetry analysis of monoclinic, orthorhombic, and trigonal M3X2-type superstructures that can be formed in strongly stoichiometric MX y compounds with B1 structure is carried out. Channels of order-disorder transitions MX y → M3X2 are determined. It is shown that, as temperature decreases, two physically admissible sequences of transformations associated with the formation of M3X2 superstructures are possible in nonstoichiometric MX y compounds of group IV transition metals. By an example of vanadium carbide VC y , it is demonstrated that orthorhombic or monoclinic V3C2 superstructures can be obtained with the formation of a nanostructure. |