Consideration on the applicability of intermetallic compounds with a large coordination number as thermoelectric materials on the basis of the calculated electronic densities of states

Abstract

The applicability of intermetallic compounds with the following types of structures as thermoelectric (TE) materials are discussed on the basis of the calculated electronic densities of states: NaZn/sub 13/-, BaCd/sub 11/-, Mn/sub 12/Th-, Ni/sub 17/Th/sub 2/-, Zn/sub 17/Th/sub 2/-, and CaCu/sub 5/- type structures. RZn/sub 12/, (R: heavier rare earth (RE) metal) and R'Zn/sub 11/ (R': lighter RE metal) can be the candidates for the n-type and p-type TE materials, respectively, if Mott's theory for the Seebeck coefficients of 3d metals is valid for f-metals and compounds. YbZn/sub 13/ and YbNi/sub 5/ are also promising because the direct contribution of the 4f-electrons to the conduction may cause an anomalous conduction behavior of the higher thermoelectric power factor. LaCo/sub 13/, and Y/sub 2/Co/sub 17/ are attractive for the additional contribution of magnetic ordering to the entropy of the compounds that can be expected along with the magnon-drag effect.