It is possible to determine the strength of the nuclear charge by the oxidation number of the atom.
Most of the physical and chemical properties of the elements can be explained on the basis of electronic configuration.
It is known that the magnitude of ionization potential depends upon the following factors: In the periodic table, effective nuclear charge decreases down a group and increases left to right across a period.
The reason why it is not 26 is that some of the electrons in the atom end up repelling the others, giving a net lower electrostatic interaction with the nucleus.
Effective atomic numbers are useful not only in understanding why electrons further from the nucleus are so much more weakly bound than those closer to the nucleus, but also because they can tell us when to use simplified methods of calculating other properties and interactions.
In this case, the effective nuclear charge can be calculated by Coulomb's law.
[2] These algebraic rules are significantly simpler than finding shielding constants using ab initio calculation.
where Updated effective nuclear charge values were provided by Clementi et al. in 1963 and 1967.
[3][4] In their work, screening constants were optimized to produce effective nuclear charge values that agree with SCF calculations.
In contrast, the effective nuclear charge is the attractive positive charge of nuclear protons acting on valence electrons, which is always less than the total number of protons present in a nucleus due to the shielding effect.