This video lecture from Transition Elements (F.Sc. second year Chemistry) covers: Physical explanation of color formation in our eyes. Geometry of 5 d sub-orbitals (T2g & Eg). The increase in size of Mn ion because of shielding effect by Eg sub-orbitals on the ligands. The transfer of electron from Eg to T2g and vice versa causing absorption of visible part of E.M spectrum forming colored compounds. Find more e-learning material and educational video lectures in Urdu at maktab.pk. These videos are free to use for promotional and commercial purpose by keeping the credits to Maktab.