K 72 Konyaeva, M. A. Electronic Structure, Magnetic Properties, and Stability of the Binary and Ternary Carbides (Fe,Cr)3C and (Fe,Cr)7C3 / M. A. Konyaeva, N. I. Medvedeva // Physics of the Solid State. - 2009. - Vol. 51, № 10. - P2084-2089 : il. - Bibliogr. : p. 2088-2089 (29 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): КАРБИД ЖЕЛЕЗА -- КАРБИД ХРОМА -- КАРБИДЫ БИНАРНЫЕ -- КАРБИДЫ ТРОЙНЫЕ Аннотация: The structural, electronic, and magnetic properties of the binary and ternary carbides (Fe,Cr)3C and (Fe,Cr)7C3 have been investigated within the ab initio density functional theory. The crystal structure of the binary carbides has been optimized and the preferred positions for replacement of chromium or iron impurities in the corresponding carbides have been determined. The changes in the electronic structure and magnetic properties have been investigated, the formation energies of the ternary carbides as functions of the impurity concentrations have been calculated, and conclusions have been drawn regarding the influence of the impurity on the stability of the carbides under investigation Полный текст |
E 27 Effect of Chromium on the Electronic Structure and Magnetic Properties of Cementite / N. I. Medvedeva, I. R. Shein, M. A. Konyaeva, A. L. Ivanovskii // The Physics of Metals and Metallography. - 2008. - Vol. 105, № 6. - P568-573 : il. - Bibliogr. : p. 572-573 (24 ref.) Рубрики: ХИМИЧЕСКИЕ НАУКИ Кл.слова (ненормированные): ХРОМ -- МАГНИТНЫЕ СВОЙСТВА -- ЦЕМЕНТИТ Аннотация: Using ab initio methods, the influence of chromium on the electron structure and magnetic properties of cementite Fe3C has been investigated depending on the chromium concentration and the possibility of the formation of a chromium carbide Cr3C has been considered. It has been established that it is the general positions of iron in the lattice of cementite that are most energetically preferable for the substitution by chromium. Chromium leads to a strengthening of interatomic interactions and the change in the sign of the enthalpy of formation in the Fe3 –xCrxC system at x= 1.9. The magnetic moments at the atoms of chromium and iron are oriented antiferromagnetically and the total magnetization of the alloyed system decreases with increasing chromium concentration Полный текст |