“…The data of Ag-, Na-, and K- doped PbSe with p-type conduction from literature are also included for comparison. If we assume that carriers are mostly scattered by acoustic phonons, under a single parabolic band (SPB) model, − a Pisarenko plot with an effective mass ( m *) of 0.28 m e ( m e is the inertial mass of electrons) is obtained through the following expressions − where r denotes the scattering factor ( r = −1/2 for acoustic phonon scattering), k B , e, η, p , and F n (η) are Boltzmann constant, elementary charge, reduced Fermi level, carrier concentration, and Fermi integral, respectively. The calculated Pisarenko plot could reasonably describe the variations of S for almost all the samples except the Sn-containing ones, see the orange curve.…”