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I read that it is because it is easier to ionise the elements as the electrons involved are those of d orbitals which have same degeneracy. First of all, i found it very vague. Secondly, what about the poor screening effect of d and f orbitals which increases effective nuclear force on valence electrons? Would it seemingly not make difficult for the ion to bear more positive charges?


marked as duplicate by Mithoron, Zhe, A.K., Todd Minehardt, Waylander Apr 4 at 8:33

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