1-ethyl-2, 6-dimethyl-4 hydroxy pyridinium magnesium sulphate tetra hydrate (EDMPMS) has been synthesized and the single crystals were grown by slow evaporation technique. The grown crystals were characterized by elemental analysis, FTIR and FT NMR techniques to confirm the formation of the compound. Thermal stability has been investigated by TG/DTA, DSC and the melting point is 113 °C. The optical transmittance window in MeOH solution was found to be 262 - 800 nm by UV - Visible spectrocopy. The second order nonlinear optical property was studied by Kurtz-Perry technique. Impedance and dielectric measurements were performed for the frequency range 42 Hz – 5 MHz at 303 K.
