Investigation on nucleation, growth and physical properties of low soluble 4-N, N-dimethylamino-4-N'-methylstilbazolium 4-aminotoluene-3-sulfonate crystal-A potential NLO material

Terahertz generation requires materials with excellent nonlinear optical (NLO) properties and environment stability. 4-N, N-dimethylamino-4-N'-methylstilbazolium 4-aminotoluene-3-sulfonate (DAAS) an organic ionic compound is found to match these conditions but it is one of the sparingly soluble compounds among the stilbazolium derivatives causing difficulty in crystal growth. Therefore, in this article, the nucleation and growth kinetics of DAAS in different solvents are examined in order to understand and improve its crystal growth. The structural properties like symmetry, hydrogen bonding that contribute to crystal growth and morphology are studied and discussed. As nonlinear optical properties in organic compound is affected by vibration of the molecules, the existence of functional groups and various modes of vibration present in the molecule are identified and categorized by Fourier transform infrared (FT-IR) and FT-Raman analyses. Linear optical properties of the DAAS at molecular level, liquid and solid phases are investigated using density functional theory and UV-Visible spectroscopic technique. The NLO properties of DAAS molecule like the first order hyperpolarizability and mean polarizability is predicted using density function theory and the second harmonic generation efficiency is determined using Kurtz powder test. The thermal stability of DAAS is compared with other highly nonlinear optical stilbazolium derivatives. (c) 2021 Elsevier B.V. All rights reserved.

Automated summary

This article investigates the nucleation and growth kinetics of the organic ionic compound DAAS in different solvents to improve its crystal growth, analyzing the structural properties and vibration modes contributing to crystal growth. The linear optical properties of DAAS at molecular level, liquid and solid phases are studied using density functional theory and UV-Visible spectroscopy, while the nonlinear optical properties are predicted using density function theory and Kurtz powder test. Comparisons are made regarding the thermal stability of DAAS with other highly nonlinear optical stilbazolium derivatives.