作者:Enrique R. Losilla、Aurelio Cabeza、Sebastián Bruque、Miguel A.G. Aranda、Jesús Sanz、Juan E. Iglesias、José A. Alonso
DOI:10.1006/jssc.2000.8984
日期:2001.1
α-Ge(HPO4)2·H2O has been hydrothermally prepared and its thermal behavior has been studied by DTA and thermodiffractometry. Three pyrophosphates can be obtained on heating at high temperature. α-GeP2O7 is protocrystalline with a layered structure related to that of the pristine material. α-GeP2O7 transforms to β-GeP2O7 above 950°C and this yields γ-GeP2O7 above 1000°C. However, γ-GeP2O7 could not be
水热法制备了α- Ge(HPO 4)2 ·H 2 O,并通过DTA和热衍射法研究了其热行为。在高温下加热可获得三种焦磷酸盐。α- GeP 2 O 7是原晶,具有与原始材料有关的层状结构。在950°C以上时,α- GeP 2 O 7转变为β- GeP 2 O 7,在1000°C以上时,生成γ- GeP 2 O 7。但是,γ- GeP 2 O在高温和环境压力下,不能将7制备成单相,因为P 2 O 5会部分释放,导致被最终的热分解产物Ge 5 O(PO 4)6污染。γ -GeP 2 ö 7已经通过加热合成为单相α -GeP 2 ö 7在20千巴和1000℃。γ- GeP 2 O 7,以前报道为立方晶,是单斜晶,a = 22.8647(4)Å,b = 22.8783(4)Å,c= 22.9429(4),β = 90.328(1)°,V = 12001.3(4)3和对称性P 2 1 / ç或降低。具有简单化学计量的γ-