Binding energy of the transition elements in the 3d series increases up to vanadium then drops from chromium to manganese and then increases slightly and then drops again
It is seen that binding energy increases up to vanadium family because of increase in the number of unpaired electrons in the 3d orbital then it is very low in case of Mn because it's partially filled d orbital does not contribute to metallic bonding and it is low for Cu and Zn because they have very few number of unpaired electrons in the 3d orbital
My question is why is the binding energy increasing with the increase in the number of unpaired electrons why can't the paired electrons of d orbital contribute to the metallic bonding
My 2nd question is both chromium and manganese have partially filled d orbital which is stable so it's electrons are not contributing to the metallic bonding then why chromium has higher binding energy than manganese shouldn't they have almost same hiding energies
