Conclusions
Single crystal specimens of GdB6 free from inclusions of the tetraboride phase were produced. This was achieved using a shielding medium with a relatively low excess pressure of argon ensuring at the same time the high homogeneity of the melt of the zone as a result of intensive stirring.
Because of the high work function of the electron of GdB6 and the instability of this phase at high temperatures, this material is not interesting as a thermoemitter of the electrons. On the other hand, it is desirable to examine in greater detail the tetraboride phase whose thermoemission properties may prove to be considerably higher than those of the hexaboride phase.
The region of antiferromagnetic ordering (15.2°K) was characterized by a large jump of the specific electrical resistivity which characterizes the structural phase transformation. At T ∿ 7–10°K an additional anomaly of the resistivity accompanied by a temperature hysteresis was detected.
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Translated from Poroshkovaya Metallurgiya, No. 7(319), pp. 54–59, July, 1989.
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Lazorenko, V.I., Siman, N.I., Dmitriev, A.I. et al. Growth of single crystals of GdB6 and examination of their properties. Powder Metall Met Ceram 28, 555–559 (1989). https://doi.org/10.1007/BF00794870
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DOI: https://doi.org/10.1007/BF00794870