所有二元系统钙,锶,钡,或Eu(甲)与Tt的(tetrel)= Si或Ge,以及锶的Sn形成二进制的Cr 5乙3个型阿5 Tt的3个相和对应的三元氢化物具有填充的Cr 5 B 3-(Ca 5 Sn 3 F-)型结构。所有经过测试的Ca–Si,Ba–Si,Ca–Ge也会产生同型A 5 Tt 3 F x相。Ca 5 Si 3,Ca 5 Si 3 F 0.42,Sr的四方结构5 Si 3,Eu 5 Si 3 H x,Ca 5 Ge 3,Ca 5 Ge 3 H x,Ca 5 Ge 3 F 0.66(I 4 / mcm,No.140)和Ba 5 Si 3 F 0.16(P 4 (ncc,Ba 5 Si 3型)。间隙中的H,F原子结合在狭窄的四面体(A 2+)4中Cr 5 B 3型重原子结构中的空穴,可以理想地描述为(A 2+)5(Tt 2)6-(Tt)4-。根据晶格常数差异,或者对于Sr 5 Si
The phase diagram of the Ca-Ge system has been investigated across the 0-70 at.% Ge range using differential thermal analysis, metallographic analysis, X-ray diffraction and electron microscopy. Four intermediate phases have been confirmed: Ca2Ge (anti PbCl2-type), Ca5Ge3 (Cr5B3-type), CaGe (CrB-type) and CaGe2 (CaSi2-type). Ca7Ge6, not previously known, is a new representative of the Ca7Sn6-type orthorhombic structure. Four eutectics occur in this system: at about 3 at.% Ge and 780 degreesC, 47 at.% Ge and 1155 degreesC, 66 at.% Ge and 840 degreesC, 76 at.% Ge and 745 degreesC. (C) 2002 Elsevier Science B.V. All rights reserved.