What informations are conveyed from the electronic configuration of the molecule?

The information is conveyed from the electronic configuration.
(a) From the electronic configuration, it is possible to find out the number of electrons in bonding molecular orbitals (N_b) and a number of electrons in anti-bonding orbitals (N_a).
(i) The molecule is stable if N_b > N_a.
(ii) The molecule is unstable if N_b < N_a.
(iii)  The molecule is unstable if N_b = N_a.
It may be noted that even if the number of electrons in bonding M.O. and the number of electrons in anti-bonding M.O. are equal, the atoms do not combine to form a molecule. This is because of the fact that the destabilising effect of anti– bonding electrons is slightly more than the stabilising effect of bonding electrons.

(b) To predict the magnetic behaviour of molecules i.e. if all the electrons in a molecule are paired, the substance is diamagnetic and in case there are unpaired electrons in a molecule, the substance is paramagnetic.