The classical trajectroy Monte Carlo method is empolyed to calculate the charge transfer cross sections and the n shell distribution of capture electron for the collision of ions with hydrogen.For the collision of partial ionized ions with hydrogen,a q-scaled cross section is obtained by introducing the reduced variables.The present results are in good agreement with experimentally measured results.

A fully relativistic distorted-wave Born theory for calculating electron impact excitational cross sections of highly charged ions is presented. Some calculation results are also given and compared with other calcultions.

Following the preceding paper(Ref.[I]),an improved method is presented for calculating the integrals in electron-atom colllisions by transforming the integration contours into complex plane.This method can calculate the integrals accurately not only for cases like Ref[I],but also for the case of"nearly degenerate"which cannot be calculated by methods given in Ref[I].The caleulational accuracies have been compared and checked to be very high.

In electron-atom (or ion) collisions, it is unadvoidable to compute a large number of integrals with seriously oscillatory wavefunctions. Since direct numerical integration are very exhausted and often may fail to reach the required accuracy, analytical methods are necessary. In this paper an improved method is presented for calculating integrals with seriously osillatory in tegrands. The accuracy of phase calculation is improved for the case of wavenumber being different. The analytical expressions of integrals are given for the case of wavenumber being equal. The accury of simulation results are very satisfactory.