Фазовая диаграмма системы Br-Cu

К оглавлению: Другие диаграммы (Others phase diargams)


Br-Cu (Bromine-Copper) P.R. Subramanian and D.E. Laughlin No Cu-Br phase diagram is available, but two intermediate phases have been reported. CuBr was reported to exist in three polymorphic modifications-CuBrIII, CuBrII, and CuBrI (nomenclature accepted from [68Rap]). Low-temperature CuBrIII transforms to CuBrII at 385 C [52Hos, 57Wag, 68Rap], and CuBrII transforms to CuBrI at 469 to 470 C [52Hos, 52Kru, 57Wag, 68Rap]. Although the transformation temperatures from the various reports are in fairly good accord, there is some disagreement in the observed melting point of CuBrI, which is accepted as 488 C. [64Van] reported two pressure-induced transitions in CuBr at ~47 kbar, positioned ~0.1 kbar apart, and a third transition at ~80 kbar. Temperature- pressure relationships in CuBr were studied by [61Edw] from 47 to 140 kbar and by [68Rap] from 0 to 40 kbar. The results of [61Edw] show two pressure- dependent transitions near 50 kbar, spaced 5 kbar apart, and two other transitions between 80 and 95 kbar. [68Rap] showed the existence of a triple point at 6.1 kbar and 413 C involving the CuBrIII+CuBrII+CuBrI equilibrium. The melting point of cupric bromide, CuBr2, is 498 C. 22Wyc: R.W.G. Wyckoff and E. Posnjak, J. Am. Chem. Soc., 44, 30 -36 (1922). 25Bar: T. Barth and G. Lunde, Norsk. Geol. Tidsskr., 8, 281-292 (1925); reported in [55Swa]. 42Veg: L. Vegard and G. Skofteland, Arch. Math. Naturvidenskab., 45(14), 163- 192 (1942) in German. 52Hos: S. Hoshino, J. Phys. Soc. Jpn., 7(6), 560-564 (1952). 52Kru: J. Krug and L. Sieg, Z. Naturforsch. A, 7, 369-371 (1952). 55Swa: H.E. Swanson, R.K. Fuyat, and G.M. Ugrinic, NBS Circular, 539(4), 36-37 (1955). 57Wag: J.B. Wagner and C. Wagner, J. Chem. Phys., 26(6), 1597-1601 (1957). 61Edw: A.L. Edwards and H.G. Drickamer, Phys. Rev., 122(4), 1149-1157 (1961). 64Van: A. Van Valkenburg, J. Res. Natl. Bur. Stand A, 68(1), 97-103 (1964). 68Rap: E. Rapoport and C.W.F.T. Pistorius, Phys. Rev., 172(3), 838-847 (1968). 73Mei: V. Meissalo and M. Kalliomaki, High Temp.-High Press., 5(6), 663-673 ( 1973). Submitted to the APD Program. Complete evaluation contains 1 figure, 5 tables, and 21 references. 1