An organic-inorganic NLO single crystal was grown using conventional and slow cooling method or ATR (Assembled temperature reduction method). Properties of as grown crystal were tried to modify using swift heavy ion (Au3+) of various fluences ranging from 1013 ions/cm2, to 1014 ions/cm2. Dielectric property of orthorhombic crystal was studied. It was noticed that, as ion fluence increases the dielectric constant of as grown material also increases. Hardness of the undamaged and swift heavy ion irradiated crystals was studied. It was concluded that the ability of resistance of deformation of swift heavy ion implanted crystal increases with increase of ion fluences. Thermal studies were carried out and it was observed that irradiated crystal exhibits increased thermal stability with increase of ion energy and this was owing to decreased degree of crystallinity.