The effect of V substitution on the properties of CoTiSb

Abstract Electrical resistivity, structural and magnetic properties of polycrystalline samples of a half-Heusler alloy, CoTiSb, and the effect of the substitution of V for Ti on these properties in CoTi 1 - x V x Sb have been investigated. The temperature dependence of the electrical resistivity in CoTiSb above 10 K is found to exhibit, on the whole, semiconducting behavior, which agrees with previous results. For samples in which V is substituted for Ti with x ⩽ 0.1 the structure is found to be the half-Heusler type as with x = 0 . As V increases from x = 0 to 0.05, the magnitude of the resistivity increases, but the temperature dependence is similar to that of x = 0 . For the sample with x = 0.1 , however, the magnitude of the resistivity suddenly decreases to the value smaller than that of x = 0 , and the slope of the temperature dependence of the resistivity becomes positive down to 25 K.