This page can help you easily determine parameters of localized states using "Mott's spectroscopy" method . This method based on independent measurements of temperature dependence of conductivity and field dependence of magnetoresistance of the same specimen and firmly established to be valid in the case of some amorphous semiconductors (e.g. a-GaSb). Because we perform such calculations rather frequently I decide to create this "one-click" web-based calculator (& brief reference). You should determine coefficients A and B as a slope of curves Ro(T) and Ro(H) in appropriate linearizing coordinates, specify the value of T which is ambient temperature for Ro(H) measurements, then fill following form and press "Calculate" button.