Effect of Mg+2 or Zn+2 ion on melatonin – DFT treatment

Effects of dications of magnesium and zinc atom(s) on melatonin, a nocturnal hormone, have been investigated within the constraints of density functional theory at the level of B3LYP/ 6-31++G(d,p). The results revealed that the composites considered (like melatonin and its dication) are exothermic and favorable in terms of Hº and Gº values. Also they are electronically stable. Various structural, quantum chemical and spectral (IR and UV-VIS) data are collected and discussed. In each case, interaction with melatonin, the cations possessed less positive charge than the initial charge of +2 that means some electron population has been transferred from melatonin to the cation. However, in the case of zinc dication composite, some bond density exists between the organic and inorganic components.