The Thermoelectric Properties of Mixed Crystals of Mg[sub 2]Ge[sub x]Si[sub 1−x]

The purpose of this work was to determine the thermoelectric properties of the pseudobinary system . The compositions investigated were , , , , , and . X‐ray diffraction lattice parameter measurements and differential thermal analysis measurements established the existence of complete solid solubility between and . Both the lattice parameter and liquidus temperature show almost linear variation with composition in this system. The melting temperature of was found to be , while that of was found to be . Electrical resistivity and Hall effect measurements indicated that at 300°K the electron Hall mobility in the mixed crystals is essentially the same as that of the pure compounds. Maximum values obtained were slightly above 300 cm 2 volt sec. The forbidden energy gap appeared to vary monotonically from about 0.78 electronvolt (ev) for to about 0.70 ev for . Thermal conductivity measurements on the pseudobinary system showed that the lattice thermal conductivity of the solid solutions is substantially lower than that of either of the pure compounds at 300°K. At this temperature the lattice thermal conductivity of was found to be 0.0268 watt/cm °K. The maximum thermoelectric figure of merit which could be obtained with these materials is not as good as that of other materials now in use.