Margo, no one knows - it is a function of temperature and doping and will in general be material specific. The virtue of using Boltztrap Is that one can compute the thermopower without needing to know the value. You can make an estimate if you have published values of the mobility for the material at hand, but in general estimating the relaxation time from first principles is a hard problem. - David -----Original Message----- From: wien-bounces at zeus.theochem.tuwien.ac.at [mailto:wien-boun...@zeus.theochem.tuwien.ac.at] On Behalf Of Malgorzata Bukala Sent: Thursday, October 06, 2011 10:32 AM To: wien at zeus.theochem.tuwien.ac.at Subject: [Wien] (no subject)
Dear users of Wien2k, I have a question about BoltzTraP code. In this program to simplify the Boltzmann equation the relaxation time approximation is adopted and relaxation time is kept constant. But what is the value of this parameter? Margo
