Why UFexAl12− x phase does not crystallize with ThMn12-structure type, when x= 2? Academic Article uri icon

abstract

  • The crystallographic structure of recently reported orthorhombic UFe 2 Al 10 phase, which belongs to the YbFe 2 Al 10-structure type is different from the well known tetragonal UFe x Al 12− x (3< x< 8) having ThMn 12-structure type. Comparative Density Functional Theory (DFT) study of the relative stability of the orthorhombic UFe 2 Al 10 phase with respect to different models of tetragonal ThMn 12-type structures with the same composition is carried out to explain this unusual phenomenon. It is shown that the fine interplay between the overlapping of 3d-states of Fe and 5f-states of U in the region− 2.5÷− 0.3 eV below the Fermi energy dictates the lower total energy of orthorhombic UFe 2 Al 10 phase in comparison with tetragonal UFe 2 Al 10 phase crystallized in ThMn 12 structure. On the example of UFe 2 Al 10 it is also directly demonstrated that DFT calculations in the framework of the Full …

publication date

  • January 1, 2011