The outer electron configuration of Gd (Atomic No.: 64)

The outer electronic configuration of gd is 4f35d56s2 due to half filled d orbital which makes it exceptionally stable

 

 

Z=64

 

symbol:Gd

 

block : F block

 

period: 6 period

 

Electronic configuration

 

expected: [Xe]4f 8 6s 2

 

observed:[Xe]4f7 5d1 6s2

 

Reason: Half filled f orbital is more stable than partially filled f orbital and since energy difference is not much between 4f orbital and 5d orbital thus 1 electron from 4f orbital(expected to have 8e) jumps to 5d orbital making it 5d1 thus deviating from the expected configuration and conferring stability through hund’s rule of maximum multiplicity.

Vg