Growth and characterisation of a third order nonlinear optical crystal 4-Dimethylamino pyridinium p-bromophenolate

•4DMAPBP crystal belongs to the monoclinic crystal system with p 21/c space group.•4DMAPBP crystal exhibits third order optical nonlinear properties.•The crystal exhibits wide transmission window width cut-off wavelength at 325 nm.•Laser damage threshold value of 4DMAPBP was observed as 2.34 GW/cm2.•4DMAPBP show positive photoconductivity making it suitable for producing mobile charge carriers. Slow evaporation method was applied for the successful growth of novel nonlinear optical crystal 4-dimethylamino pyridinium p-bromophenolate (4DMAPBP) using ethanol as solvent at room temperature. Single crystal X-ray diffraction studies show that the grown 4DMAPBP crystalizes in the monoclinic crystal system with P21/c space group. Fourier transform infrared spectroscopy (FTIR) and Fourier transform Raman spectroscopy (FT- Raman) spectral analysis confirms the functional group of the crystal 4DMAPBP. Thermogravimetric analysis (TGA)/ Differential thermal analysis (DTA) analysis enriches the thermal firmness of the material. The mechanical hardness of 4DMAPBP was investigated by using Vicker's microhardness test. The transmittance spectra recorded for the sample near the visible and IR region (320–1000 nm) reveals it suitability for non-linear optical applications. The real part and imaginary part of the of the third order susceptibility of the crystal were found to be 1.96 × 10−8 esu and 2.267 × 10−7esu. The Laser damage threshold value was observed as 2.34 GW/cm2 for the 4DMAPBP crystal. Positive photoconductivity of the crystal has been revealed.