Influence of Picric Acid on SHG Efficiency of Tris (thiourea) Zinc(ii) Sulphate (ZTS)

The influence of picric acid on second harmonic generation (SHG) of tris (thiourea) zinc(II) sulphate (ZTS) crystal is investigated. ZTS, a potential semi-organic nonlinear optical material, is doped with picric acid (1:1). Good quality crystals in the presence and absence of picric acid are grown by slow evaporation solution technique. XRD and FT-IR spectral analyses confirm that there is slight distortion in crystal structure due to doping. The surface morphology of the as-grown specimen which is changed with the nature and concentration of dopant is studied by scanning electron microscopy. TG–DTA study reveals that the sample is pure and there is no decomposition up to the melting point. Single crystal XRD indicates that the inclusion of picric acid is not to an appreciable extent. The SHG efficiency of the crystal is decreased substantially by the dopant.