A facile growth, optical behavior of organic nonlinear optical crystal: 4-bromo-2-methylbenzonitrile

4-bromo-2-methylbenzonitrile single organic nonlinear optical crystal was prepared at room temperature by the slow evaporation method. The grown crystal’s crystalline nature was verified, and the unit cell characteristics are provided as a = 4.08 Å, b = 6.61 Å, c = 28.93 Å, α = 90°, β = 90°, γ = 90°. The functional groups of the crystal were identified using the FTIR and FT-Raman spectra. UV–Vis optical studies show UV cutoff wavelength at 221.6 nm, and the bandgap of the grown crystal was estimated at 4.87 eV using the Taucs’ plot. Photoluminescence spectra exhibited violet and red emissions. A high dielectric constant was received at a low frequency. The TG/DTA curve shows that the grown crystal was stable up to 125.59 °C. The Kurtz-Perry powder technique was applied to confirm the Second Harmonic Generation’s nature. By using the agar diffusion method, the antibacterial property of the grown 4B2MBN crystal was determined.