Cations with 18 electrons shell configuration cause greater polarization than the cations with 8 electrons shell configuration with the same size and chargeplease explain this..!!!!

In cations with 18 electrons shell configuration (pseudo noble gas configuration), the d-electrons are poor in shielding. Hence, the nuclear charge can cause more polarization of the anion in the case of cations with pseudo noble gas configuration than in the case of cations with 8 electrons in the outer shell. This increases the covalent character in compounds with such cations.

 

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