Thermoelectric Power of Hg₂․₈₆AsF₆

Abstract

<p>An apparatus was developed to measure the Seebeck e.m.f. of small specimens which have to be handled in a dry-box and to which only mechanical contact can be made. The method is successful if the electrical conductivity of the contacts is much larger than that of the sample. Utilizing this apparatus, the temperature dependence of the thermopower of Hg₂․₈₆AsF₆ was investigated along its two principal directions. Metallic conduction was found which is electron dominated in the a,b directions and hole dominated in the c direction. Therefore, the temperature dependence observed in the thermopower is explained using the free electron model, in which the total thermopower is expressed as the sum of a diffusion component, dominating above 100 K, and a phonon drag component dominating below 100 K. Thus, the Fermi energy is calculated to be 4.6±0.5 eV and the Debye temperature is fixed between 60 K and 90 K.</p>