D.Kalaivani, Mrs.M.Indirani & Dr.A.Mukunthan
L-histidine bromide (LHB), semi organic non linear optical (NLO) crystals having good optical transmission in the entire visible region and hence it is a potential material for non linear frequency conversion. LHB is Biaxial crystal which crystallizes in the orthorhombic structure with space group P212121 with lattice parameter value a = 7.0530�º, b = 9.0409�º, C=15.2758�º. In the present study , both classical nucleation theory and the modified classical nucleation theory have been employed to study the nucleation parameters of LHB crystal. A comparative study has been made and the result are analyzed. From the study of nucleation parameters the critical super saturation Sc is fixed in order to grow good quality single crystals.