Single crystal growth of 1,2,3-Benzotriazole 3,5-dinitrobenzoic acid (BTNBA) by slow evaporation solution technique (SEST) for nonlinear optical (NLO) applications

Abstract

The organic single crystal of 1,2,3-benzotriazole 3,5-dinitrobenzoic acid was synthesized and grown by slow evaporation solution technique (SEST) for the first time reported in the literature. The lattice parameters of the grown crystal were confirmed by single crystal X-ray diffraction analysis. Using powder X-ray diffraction analysis, miller index and (h k l) planes were identified. The 1H NMR and 13C NMR spectral analysis was used to confirm the chemical environment of various protons and carbons present in a BTNBA structure. The optical quality of the grown crystal was identified by the UV–Visible NIR spectrum analysis. The grown crystal has good optical transmittance in the range of 400 –800 nm. Functional groups of BTNBA crystal were confirmed by Fourier Transform Infrared spectrum analysis. The thermal behaviour of the BTNBA crystal was investigated by thermogravimetric and differential thermal analysis. The photoconductivity analysis was carried out to calculate the photo and dark current values. Intermolecular interactions of BTNBA are executed by the Hirshfeld surface analysis. Vickers microhardness analysis was carried out to identify the mechanical stability of the grown BTNBA crystal. The dielectric constant (ε') and dielectric loss (tan δ) as a function of frequency were measured for the grown crystal. The third-order nonlinear optical properties such as nonlinear refractive index (n2), absorption co-efficient (β) and susceptibility (χ(3)) were studied by Z-scan technique at 632.8 nm using He-Ne laser. The crystal grown by the SEST method shows high mechanical strength, and good third order nonlinear susceptibility with less defects which makes it suitable for photonics and optical limiting.