Electrical properties of liquid Te-RE (RE=Ce, Sm, Er) alloys

When Ce, Sin and Er are added to liquid Te, the electrical conductivity, a, and the thermoelectric power, S, of the liquid alloys are observed to decrease rapidly and to increase gradually, respectively, with increasing RE (RE = Ce, Sm, Er) composition. The composition dependences of a in liquid Te-Ce, Te Sm and Te-Er all approach zero at the stoichiometry RE(2)Te(3). The similar composition dependences of a suggest that the 4f electrons of the RE ions weakly interact with the conduction electrons. The a and S of liquid Te-RE alloys are analyzed by the pseudogap model of liquid semiconductors. According to this model, the density of states, N(E(F)), at the Fermi level decreases smoothly with increasing RE composition and its gradient value, dN(E(F))/dE, is weakly dependent on the RE composition. (C) 2002 Elsevier Science B.V. All rights reserved.