Effect of nonorthogonality of wavefunctions of the intial and final states on the electron-capture reaction cross sections

We analyze numerically the overlap integral of wavefunctions of the initial and final electron states in capture reactions $He^{2+} + H\to He^{+} + H^{+}$ and $Li^{3+} + H\to Li^{2+}+ H^+$ in the energy range of the incident ion 20-100 keV/nucleon. The calculations show that the overlap integral must be taken into account only in the analysis of electron capture from the 1s shell of the target to the 1s shell of the incident ion.