INTERNAL CONVERSION COEFFICIENTS - HOW GOOD ARE THEY NOW?

Internal conversion coefficients involving atomic electrons (ICC) and electron-positron pairs (IPC) are often required to determine transition multipolarities and total transition rates. A new internal conversion coefficient data base, BrIcc has been developed which integrates a number of tabulations on ICC and IPC, as well as (Omega)(E0) electronic factors. To decide which theoretical internal conversion coefficient table to use, the accurately determined experimental αK, αL, αTotal and αK/αL values were compared with the new Dirac-Fock calculations using extreme assumptions on the effect of the atomic vacancy. While the overall difference between experiment and theory is less than 1%, our analysis shows preference towards the so called ''Frozen Orbital'' approximation, which takes into account the effect of the atomic vacancy.