attained by transfer of an electron from d xy to d yz with small energy difference (143.7 cm -1 ), leading to significant positive contribution to the D value. Thus, although the overall D value is negative but the magnitude is smaller due to large positive contribution from the second excited state. In complex 3, the imidazolin ylidine ligand is substituted which, due to better π accepting ability than imidazol ylidine (in complex 2), renders more pronounced dπ-pπ interactions and hence, stabilizes the d xz orbital compared with the d z 2 and d yz which are almost degenerate (Figure ). As a consequence of this pattern of d-orbital splitting, the ground state acquires non-Aufbau electronic configuration,