Electronic transport properties — namely, conductivity, Seebeck coefficient,
and electronic component of thermal conductivity — are calculated through the
The spectral conductivity is calculated as
where α and β denote Cartesian coordinates,
εnk and vnk,α are the energy and
group velocity of band index n and wave vector k, respectively.
The spectral conductivity can be used to compute the moments of the generalized
where e is the electron charge and εF is the Fermi level at a certain doping
concentration and temperature T.
The Fermi–Dirac distribution is given by
where kB is the Boltzmann constant.
Electrical conductivity (σ), Seebeck coefficient (S), and the
charge carrier contribution to thermal conductivity (κ) are obtained as