The cation is a d-block metal ion, when a d-block metal forms a cation, the electron in the outermost ns subshell are removed, the inner (n-1)d electron become the outermost electron. Since d electron do not penetrate much into the inner core => poor screening of the +ve nuclear charge => cation becomes more polarizing
p.s. n means principal quantum no.
上面尼段野係關於 condition for polarization of ionic bond ...
我唔係好明點樣 poor screening ,,
點解又關 cation become more polarizing事??
thanks for your help