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Abstract: The phase diagram of the GeSe2–PbTe system is studied by means of X-ray diffraction, differential thermal analysis and measurements of the microhardness and the density of the material. The unit-cell parameters of the intermediate phase α-GeSe2·(2− x)PbTe, (x =0/1) were determined: a =6.200Å, b =3.807Å, and c =3.645Å, α =106.47°, β =99.85°, and γ =87.22°. The intermediate phase α-GeSe2·PbTe receives a peritectic reaction at 425°C. This phase has variable composition GeSe2·(2− x)PbTe (x =0/1), it melts congruently at 425°C and stands polymorphic transition at T α↔β =325°C, which dependents of the composition (x). The existence of a narrow regions of solid solutions based on PbTe is supposed. [Copyright &y& Elsevier]

The phase diagram of the system GeSe2–SnSe is studied by means of X-ray diffraction, differential thermal analysis and measurements of the density and the microhardness of the material. There are no intermediate compounds in it, as well as regions of range of solid solutions at room temperature on the base of GeSe2 and SnSe. There are two non-variant equilibria in the system: eutectic (where T e=530±5°C and x e= 40 mol% SnSe) and metaeutectic (where T m=550±5°C and x m=98 mol% SnSe). [ABSTRACT FROM AUTHOR]

The phase diagram of the system Ag4SSe–As2Se3 is studied by means of X-ray diffraction, differential thermal analyses and measurements of the microhardness and the density of the materials. The unit-cell parameters of the intermediate phases 3Ag4SSe·As2Se3 (phase A) and Ag4SSe·2As2Se3 (phase B) are determined as follows for phase A: a=4.495 Å, b=3.990 Å, c=4.042 Å, α=89.05°, β=108.98°, γ=92.93°; for phase B: a=4.463 Å, b=4.136 Å, c=3.752 Å, α=118.60°, β=104.46°, γ=83.14°. The phase 3Ag4SSe·As2Se3 and Ag4SSe·2As2Se3 have a polymorphic transition α↔β consequently at 105 and 120°C. The phase A melts incongruently at 390°C and phase B congruently at the same temperature. [ABSTRACT FROM AUTHOR]

The phase diagram of the system CdI2-Bi2O3 is studied by means of X-ray diffraction, differential thermal analysis and measurements of the density of the material. As a result of the synthetic and peritectic interactions, two incongruently melting intermediate phases i.e. phase A - CdI2·2Bi2O3 and phase B - CdI2·4Bi2O3 (stable in the temperature interval 370-850°C) are formed. The phase A exists in two polymorphic forms with a temperature of the phase transition Ta↔b=320-370°C. The unit cell parameters at low temperature modification of a-CdI2·2Bi2O3 were determined. (a=1.032 nm, b=1.046 nm, c=1.046 nm, α=115.02°, β=109.11° and γ=82.04°). The phases A and B have fields of homogeneity. [ABSTRACT FROM AUTHOR]

The phase diagram of the system GeSe2-SnTe is studied by means of X-ray diffraction, differential thermal and measurements of the microhardness and the density of the material. The unit-cell parameters of the intermediate phases α-3GeSe2·SnTe (phase A) and GeSe2·2SnTe (phase B) are determined as follows for phase A: a=0.7955 nm, b=0.6969 nm, c=0.6064 nm, α=91.47°, β=85.90°; for phase B: a=0.6063 nm. The phase α-3GeSe2·SnTe melts congruently at 500°C and a polymorphic transition of the phase takes place at Tα?↔β=400°C and the phase GeSe2·2SnTe at 385°C decomposes to the peritectoidal reaction at α-3GeSe2·SnTe+SnTe. [ABSTRACT FROM AUTHOR]

The phase diagram of the system Ag4SSe-SnTe is studied by means of X-ray diffraction, differential thermal and metallographic analyses and measurements of the microhardness and the density of the material. this diagram is divided into two eutectic-type subdiagrams by the composition Ag4SSe·2SnTe. The unit-cell parameters of the intermediate phases 3Ag4SSe-SnTe (phase A) and α-Ag4SSe·2SnTe (phase B) are determined as follows: a=0.7851 nm, b=0.7196 nm, c=0.6296 nm, α=101.32°, β85.90°, γ=111.36°; for phse B:a=0.3662 nm, b=0.3303 nm, c=0.3343 nm, α=90.74°, β108.94°, γ=91.91°. The phase Ag4SSe·2SnTe melts congruently at 615°C and a polymorphic transition of the phase takes place at Tαharr;β=110°C. [ABSTRACT FROM AUTHOR]