An organic 4-(3-nitrophenylamino)-4-methylpentan-2-one picrate (3NAP) cocrystal was synthesized using slow solvent evaporation technique and its crystal structure is reported. The 3NAP compound crystallized in monoclinic crystal system with centrosymmetric space group P21/c and the cell parameters are found to be a=8.6339 Å, b=19.1965 Å, c=13.2058 Å, α=90∘, β=106.725∘, γ=90∘ and V=2096.1 Å3. Best agreement between theoretical and experimental value of CHN elemental composition confirmed inclusionless compound formation. The reasonable FWHM value of prominent peak observed from high-resolution X-ray diffraction experiment indicates superior crystallinity of 3NAP. The load-dependent hardness values measured at (010), (010), and (001) – planes of 3NAP single crystal admit its mechanical anisotropy. Further, the work hardening coefficient confirms that the title crystal belongs to the soft material category. The dark and photocurrent of the 3NAP crystal were measured, and it exhibits positive photoconductivity. The laser-induced surface damage threshold of the 3NAP crystal was found to be 7.5 GWcm−2. Nonlinear coupling between the intermolecular charge transfer and an applied optical field enhanced third order nonlinear optical properties. The intermolecular charge transfer and interactions are proved to be true in 3NAP via Hirshfeld surface analysis. The third order nonlinear optical susceptibility (χ(3)) and optical limiting threshold under continuous-wave laser excitation was measured to be 3.96 × 10−6 esu and 3.44 × 103 Wcm−2. The superior physicochemical and nonlinear optical properties promote the title material as a promising candidate for nonlinear optical device applications. © 2020 Elsevier B.V.