Q. The electronic configuration of gadolinium (atomic number ) is

 1977  220 Classification of Elements and Periodicity in Properties Report Error

Solution:

The electronic configuration of is .

Therefore, further addition of electrons occurs in a lower energy -orbital till it is exactly half filled at .

Thus, the electronic configuration of is .

Therefore, addition of next electron doesn't occur in a more stable exactly half-filled shell but occur in a little higher energy -orbital.

Thus, the electronic configuration of is