ABSTRACT

This chapter presents two ways to calculate electron transport coefficients on the basis of DFT electronic structure calculations. First, linear equations of nonequilibrium thermodynamical systems, in terms of external fields yielding charge and heat currents. Secondly, it presents the results of residual electrical conductivity σ0 and Seebeck coefficient calculations as determined from direct FS integration of k-dependent velocities, and lifetimes of electrons in chemically disordered materials. It is worth noting that in alloys, electronic bands ϵ and then FS have complex energy values with its nonvanishing imaginary part Im ϵ related to chemical disorder. The agreement is clearly good and obtains that the absolute value of the thermopower decreases as the doping electron concentration increases. Since electron transport behaviors are directly related to electronic states near the Fermi energy, searching for accurate information on k-space electron features appears particularly valuable to model or even to predict thermoelectric behaviors.