Abstract

The skutterudite-derivative phase RhGe_1.5-xSe_1.5+x has been synthesized and structurally characterized by metallography and powder X-ray diffraction data. At x = 0, RhGe_1.5Se_1.5 displays trigonal sym metry, space group R-3, with unit cell parameters a = 12.0601(8) Å, c = 14.826(1) Å, V = 1867.5(4) ų, and Z = 24. The crystal structure can be viewed as a modification of the cubic structure of the skutterudite CoAs₃, where Ge and Se anions order in layers perpendicular to the [111] direction of the cubic skutterudite unit cell. Electrical resistivity, Seebeck coefficient and thermal conductivity of the phase RhGe_1.5–xSe_1.5+x( p-type semiconductor) have been investigated for different x values in the temperature range from 3 to 640 K.