Application of Gauss quadrature formula to calculation of thermally stimulated current

In order to calculate the activation energy of dipole relaxation and electron detrapping, it is necessary to estimate thermally stimulated current (TSC) I(T). One generally uses the asymptotic series to express the exponential integral in TSC. Its main inconvenience is that for n→∞, each term goes to infinity. Although this series has properties that permit a very good approximation for exponential integral, it is divergent. For the above reasons we use a Gauss quadrature formula to estimate the exponential integral. Its marked characteristics are: high precision, fast convergence and good stability. We have applied this formula to the estimation of the activation energy of charge carrier in traps in TSC data of R. Chen