STUDY OF CARBON-SUBSTITUTED EUB6

Carbon-substituted europium hexaborides EuB6-xCx have been prepared by borothermal reduction. The homogeneity range is 0 ≤ x ≤ 0.21. The lattice parameter decreases progressively from 4.1855 Å to 4.1703 Å with rising x. The paramagnetic Curie temperature diminishes from 15 to - 6.5 K. Electrical properties have been studied for x = 0 and x = 0.05 on single crystals prepared by an Al-flux technique. Between 30 and 300 K both single crystals have metallic behavior and their resistivity at 300 K is of the order of 10-4 Ω .cm. However each single crystal shows a rather different temperature-dependence of resistivity at low temperature. © 1978.