Structural Chemistry of the Np-Ge Binary System
The structural chemistry of the complete binary neptunium-germanide system has been investigated by means of X-ray diffraction. In addition to the well-known NpGe(3) (AuCu(3) type), at least five new binary phases have been found. The crystal structure of NpGe(2-x) (defect ThSi(2) type), NpGe2-x (defect AIB2 type), NpGe (USi type), Np(5)Ge(4) (TisGa(4) type), and Np(5)Ge3 (W(5)Si(3) type) have been refined from single-crystal and powder X-ray diffraction data. X-ray powder analyses by Rietveld-type profile refinement revealed a small homogeneity range of the three first phases, as usually observed with the rare-earth or uranium isotypic compounds, whereas Np(5)Ge(4) and Np(5)Ge3 seem to be line compounds as the unit cell parameters were independent of the starting composition. The formation and the homogeneity range of these new phases are discussed, and the structural evolution is compared with the analogous uranium binary system.
Bibliographic Reference: An article published in: Journal of Solid State Chemistry 156 (2001) pp.313-320
Record Number: 200013385 / Last updated on: 2001-06-27
Original language: en
Available languages: en