A new organic framework of benzimidazole with picric acid has been synthesized. A single crystal with a size of 38 x 10 x 4 mm(3) was grown by a slow evaporation solution growth technique. X-ray diffraction study revealed that the BZP crystal belongs to triclinic system with space group P-1. High resolution Xray diffraction study shows the absence of grain boundaries without any defects. The thermal stability and specific heat capacity of BZP were investigated by TG/DT and TG/DSC analyses. From the UV-vis-NIR spectral study, optical transmission window and band gap of BZP were found out. The nonlinear refractive index (n(2)) and third order susceptibility Re(chi((3))) values of BZP crystal are estimated to be 1.73 x 10(-7) cm(2)/W and 1.26 x 10(-5) esu, respectively using a Z-scan technique. (C) 2015 Elsevier B.V. All rights reserved.