how to caluculate screenig constant

Dear student,

We know that in quite a few atoms, each of the constituent electron is said to experience less than the actual nuclear charge because of shielding or screening by the other electrons. Therefore for each electron in an atom, Slater's rules provides a value for the screening constant, which is denoted by σ.

Also, we know that the effective nuclear charge may be defined as the actual nuclear charge (Z) minus the screening effect which is caused by the electrons existing between the nucleus and the valence electron.

Therefore the effective nuclear charge would be given by Z* = Z - σ here, Z= Atomic number, σ = Shielding or screening constant.

Regards
Sumit