A set of practical parametes on hydrogenic ions is given for electron-impact excitation cross sections and rate coefficients with transitions nl→n'l',n1,2,...,7, n'=2, 3,..., 8. Application ranges are 3≤ Z ≤74;x≥2 for n'≤5;x≥20 for n'≥5. The errors are generally about 30%.

The electron impact excitation of He-like ions is studied by distorted wave method. The HFS wave functions of the target are used. We have calculated the transitions between the 1¹S and 2^1,3S, 2^1,3P states for some He-like ions. Results are presented in terms of collision strengths. The incident electron energies are from threshold to x=10. The results are compared with the data avaible. It is shown that the results are satisfied in most cases.