As reported, the halide complexes of bismuth are known to show two types of electronic bands, metal centered (MC) sp bands and halogen to metal centered LMCT bands. Generally, the LMCT transitions are observed to be higher in energy however, upon changing the halides coordinated with bismuth atom from Cl, Br to I, the contribution of higher energy LMCT transition shifts towards the lower energy side and its contribution increases in sp absorption bands (Figure ).