Investigation on structural, optical, thermal and mechanical properties of 1, 3-dinitrobenzene (1,3-DNB) single crystal

An organic 1,3-Dinitrobenzene (1,3-DNB) single crystal have been grown by Bridgman-Stockbarger method and their structural, optical, thermal and mechanical properties were analyzsed by employing powder-XRD, FTIR, optical absorption, transmission, photoluminescence, TG-DTA, microhardness and SHG measurements. The obtained results explore the well suitable nature of the grown crystal for the NLO and optolectronic applications. The crystalline nature and structural properties of the material has been confirmed by using powder X-ray diffraction (PXRD) analysis. FTIR spectral study reveals the presence of fundamental stretching and bending mode vibrations of grown 1,3-DNB crystal. Linear optical properties of the grown organic single crystal have been studied by using UV-Vis-NIR spectrum analysis, which exhibit the cut-off wavelength at 431 nm. From the tauc's plot, the calculated optical band gap energy value is 2.78 eV. The photoluminescence spectrum compresses three emission bands in the region centered at 388 nm, 452 nm and 569 nm and it is characterized through the CIE 1931 chromaticity diagram to observe the dominant emission color of the studied crystal. Thermal stability and melting point of the grown single crystal was carried out through the TG-DTA analysis. The microhardness test explores the mechanical strength of the titular crystal. Nonlinear optical efficiency of grown 1,3-DNB crystal was found to be 1.75 times greater than that of standard KDP crystal. In addition, theoretical studies of polarizability and hyperpolarizability, HOMO-LUMO energy gap and electrostatic potential (ESP) were also performed. Hirshfeld surface and two dimensional (2D) fingerprint plots were analyzsed from the crystal explorer 3.1 software and the results are discussed in detail. (C) 2019 Elsevier B.V. All rights reserved.