e is also a function of the carrier mobility (⇣), which is estimated using a semi-empirical model (Eq. 4). The error in estimating ⇣ with the model is ±1/2 order of magnitude and has proven to successfully predict e with errors below the experimental variability. The model provides an estimate of the phonon-limited, room-temperature ⇣ e . When combined with n, the roomtemperature e can be estimated.