<p>A nitroaromatic organic 2,5-dichloronitrobenzene single crystal was grown by the slow evaporation solution growth method. Single-crystal X-ray diffraction analysis is used to determine the unit-cell parameters. The powder X-ray diffraction study is carried out to identify the crystalline planes of the grown crystal. The functional groups of the grown 2,5-dichloronitrobenzene crystal were studied by Fourier transform infrared (FTIR) and Fourier transform Raman spectroscopy (FT-Raman) analyses. The UV–visible spectroscopic study reveals the linear optical transmittance of the grown crystal and the optical bandgap value is calculated as 3.19 eV. The optical parameters such as Urbach energy, refractive index, steepness parameter, and electron–phonon interaction were calculated. Thermogravimetric (TG) and differential thermal analyses (DTA) are used to analyse the thermal stability of the grown single crystal. Kinetic and thermodynamic parameters were calculated. The photoluminescence emission spectrum shows a strong and broad emission peak observed around 493 nm. Using scanning electron microscopy, the surface image of the grown crystal is analyzed. The third-order nonlinear optical absorption and the optical limiting properties of the grown crystal are studied by the open-aperture Z-scan technique.</p>