摘要:
Investigations in the Er-Ge phase diagram enable the characterization of two new erbium germanides: Er2Ge5 and ErGe2+x (x = 0.16) Both compounds have been studied by single crystal X-ray diffraction. The Er,Ge, compound is of a new type characterized by a stacking of ZrSi2 and DyGe3 blocks (S.G.: Pmmn, a = 4.0081 Angstrom, b = 3.8855 Angstrom, c = 18.288 Angstrom). The ZrSi2-type ErGe2+x compound (S.G.: Cmcm, a = 4.019 Angstrom, b = 15.843 Angstrom, c = 3.881 Angstrom) displays a partial occupation of the pyramidal holes of the ZrSi2 structure. The structural features of the ErGe3, Er2Ge5 and ErGe2+x compounds are discussed. (C) 1999 Elsevier Science S.A. All rights reserved.