Synthesis growth and Characterization of certain organic Single crystals for nonlinear optical Applications

Abstract

In the recent few decades, search of nonlinear optical (NLO) materials was increased after the invention of laser. The invention of laser has paved path to discover the nonlinear phenomena, which in turn lead to several technological applications such as optical switching, optical power limiting, optical parametric generation, high speed telecommunication and terahertz wave generation. All such technological application needs material with high nonlinearity. High NLO coefficient arises in material because of the presence of - conjugated electron systems. Organic materials are one which - conjugated system and it offers number of design possibilities over other inorganic and semi organic materials. All the above said technological applications prefers crystals due to purity and periodicity of atoms in the crystal. While developing a crystal for nonlinear application, the most important condition is that the material must possess noncentrosymmetric space group. But crystallization in noncentrosymmetric space group is still remains a difficult among the crystal grower. Nonlinear applications such as terahertz generation and Second Harmonic Generation (SHG) are possible only if the crystal holds noncentrosymmetric space group along with higher NLO coefficient. So, in this present situation for better technological and nonlinear applications, it is necessary to synthesis new materials and develop them as good quality single crystals. Hence, the present work aimed to synthesis three new organic nonlinear materials 4- nitro-benzoic acid (3-Ethoxy-2-hydroxy-benzylidene)-hydrazide (NEH), 1- ((benzylamino)(phenyl) methyl) napthalen-2-ol (BPN) and Dibenzyl-(2-methyl-4- nitro-phenyl)-amine (DMNPA). The proposed three materials were synthesized and by slow evaporation technique the single crystals were grown. Single crystal X-ray diffraction analysis was used to determine the structure of all the three grown crystals and the Crystallographic Information File (CIF) of the materials were deposited in Cambridge Crystallographic Data Centre (CCDC). newline