摘要： The furfurylaminium 2-chloro-5-nitrobenzoate (FC) is a modernized organic material possessing enhanced order three nonlinearity. The crystals of FC of dimensions 17 × 4 × 2 mm3 were yielded on slow evaporation with the usage of ethanol-water mixed solvent (1:1). The precise peaks in powder XRD analysis reveal the crystalline property of the compound. The lattice parameters was estimated (a = 11.77 ± 0.012 ?, b = 6.84 ± 0.012 ? and c = 16.33 ± 0.028 ? and volume = 1342 ?3) from powder XRD using XRDA software. The FC crystal corresponds to the system of monoclinic with the space group P21/c. The UV-visible spectrum of FC crystal sample furnishes the lower cut off wavelength (325 nm) and the band gap (3.57 eV) for FC crystal. The dispersion factors Eo and Ed was calculated to be 4.24 eV and 15.20 eV respectively from Wemple and Di Domenico single oscillator model. Using these values, the oscillator strength value was calculated to be 64.5134 (eV) 2 and the moments of optical spectra was estimated to be M -1 = 3.580 (eV) 2 and M -3= 0.198 (eV) 2. The optical conductivity (σ) value of FC crystal at 532 nm was found out to be 0.21 ×1010 s-1. A red emission peak at 691 nm was obtained in photoluminescence spectra when the FC sample was excited at 325 nm. Single shot LDT value for FC crystal was calculated to be 14.40 GW/ cm2. The third order optical susceptibility (χ(3)) of the molecule was enumerated as 4.02 ×10-6 esu from Z-scan technique and the second order hyperpolarizability (γ) value is calculated to be 2.64 × 10-35 esu. The coupling factor (ρ*) is estimated to be 0.047, on utilizing the calculated values of (Re χ(3) = 0.19 × 10-6 esu) and (Im χ(3) =0.19 × 10-6 esu) from Z scan technique. The specific heat capacity (Cp) at 50°C was calculated as 1.5810 (Jg-1 K-1) and thermal diffusivity (α) as 1.750 ×10-6 m2/s. Thus using α the thermo-optic coefficient was deliberated to be 5.34 × 10-6 K-1. The maximum output power of FC indicates its optical limiting behaviour.