On reason of difference between various calculations of the inner conversion coefficient

The calculation of internal conversion coefficient (ICC) with allowance for the absence in an atom of a converted electron is presented. The ICC calculated with accounting for a post-conversion hole in the K shell (A) are compared with those not accounting for the hole (B) and with the Hager-Zeltzer ICC. The (A-B)/(B)% ratio is calculated. The following conclusions are made: 1. The difference between ICC(A) and ICC(B) decreases with the increase of the kinetic energy Esub(kin) of a conversion electron. 2. At the Esub(kin)=1 keV the difference reaches 20% for the E5-, M5- multipoles of the K shell. 3. The difference is weakly dependent upo Z (20 <= Z <= 92) provided that the Esub(kin) remains the same. 4. The difference is maximum for the K shell. 5. There is no difference between the ICC(A) and Hager-Zeltzer ICC. 6. For the pure E2-transitions in evan-even deformed nuclei the difference between the ICC(A) and ICC(B) attains 3% in the experimental transition energy range