Isothermal section of the Gd-Mn-Ge ternary system at 1070 K

M. Konyk; L. Romaka; V.V. Romaka; Yu. Stadnyk

doi:10.15330/pcss.26.1.140-145

Authors

M. Konyk Inorganic Chemistry Department, Ivan Franko National University of Lviv, Lviv, Ukraine
L. Romaka Inorganic Chemistry Department, Ivan Franko National University of Lviv, Lviv, Ukraine
V.V. Romaka Technische Universität Dresden, Chair of Inorganic Chemistry II, Dresden, Germany
Yu. Stadnyk Inorganic Chemistry Department, Ivan Franko National University of Lviv, Lviv, Ukraine

DOI:

https://doi.org/10.15330/pcss.26.1.140-145

Keywords:

Intermetallics, ternary system, Phase equilibria, Crystal structure

Abstract

Interaction between the components in the Gd–Mn–Ge ternary system was studied at 1070 K over the whole concentration range using scanning electron microscopy, energy dispersive X-ray microanalysis and X-ray diffractometry. At 1070 K Gd–Mn–Ge system is characterized by existence of six ternary compounds: GdMn₄Ge₂ (ZrFe₄Si₂ structure type, space group P4₂/mnm, a = 0.7645(4) nm, c=0.3953(3) nm), GdMnGe (TiNiSi structure type, space group Pnma, a=0.7129(2), b=0.4166(2), c=0.8201(2) nm), Gd₃Mn₄Ge₄ (Gd₃Cu₄Ge₄ structure type, space group Immm, a=1.4023(4), b=0.7121(3), c=0.4212(3) nm), GdMn₂Ge₂ (CeAl₂Ga₂ structure type, space group I4/mmm, a=0.40326(6), c=1.0884(2) nm), GdMn₆Ge₆ (MgFe₆Ge₆structure type, space group P6/mmm, a = 0.52377(5), c = 0.8182(1) nm) and GdMn_1-хGe₂ (CeNiSi₂ structure type, space group Cmcm, a = 0.41612(8)-0.41590(7), b = 1.6123(3)-1.6119(1), c = 0.40336(8)-0.40290(6) nm). For the GdMn_1-хGe₂ compound the homogeneity range was determined (x=0.70-0.64).

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