碲化物(RuTe_2-OsTe_2)系的研究

A Study of Telluret System RuTe_2—OsTe_2

采用元素直接反应法制备了“RuTe_2—OsTe_2系”内各种成份的碲化物。借助X-射线衍射研究证实:≤5000℃下,化合物OsTe_2为纯的Marcasitetype相,经4500℃、136h热处理,生成正交晶系M-OsTe_2相,晶格参数为a=5.281×10^(-10)m,b=6.386×10^(-10)m,c=4.031×10^(-10)m;550℃为OsTe_2的两种同素异构体并存(Marcasite-type相+Pyrite-type相),600～800℃为纯的Pyrite-type相。在RuTe_2-OsTe_2系中,发现低温Marcasite-type三元化合物固溶相:M-Ru(Os)Te_2和M-Os(Ru)Te_2,以及Pyrite-type三元化合物固溶体相:P-Ru(Os)Te_2和P-Os(Ru)Te_2高温为Pyrite-type的三元连续固溶体:P-(OsRu)Te_2。

Tellurets of the system RuTe_2—OsTe_2 were prepared by heating the mixtures of pure Ru, Os and Te in evacuated and sealed quartz tube. At 400～800℃ reaction temperature interval, the system RuTe_2-OsTe_2 was investigated by X-ray. Below 500℃, the pure marcasite-type modification of OsTe_2 was obtained and identified to be an orthorhombic with a =5.281×10^(-10)m, b=6.386×10^(-10)m, c=4.031×10^(-10)m. At 550℃, OsTe_2 was found to be a mixture of pyrite and marcasite modification, which transforms monotropically into the pyrite type form at 600～800℃. For the system RuTe_2—OsTe_2, a series of ternary compounds solid solutions of the marcasite-type and pyrite-type were found at low temperature. M-Ru(Os) Te_2, M-Os(Ru)Te_2 and p-Ru(Os)Te_2. Reactions at high temperature result in forming a ternary series compounds solid solution of the pyrite-type: p-(RuOs)Te_2.