A five-coordinate chloroiron(III) complex has been synthesized and characterized by X-ray diffraction analysis and UV-Vis spectroscopy. The maximum one-photon absorption (OPA) wavelengths recorded by both linear optical measurements and quantum mechanical computations using the configuration interaction (CI) method are estimated to be shorter than 400 nm in the UV region, showing good optical transparency to visible light. To investigate the microscopic third-order nonlinear optical (NLO) behavior of the title compound, we have computed both dispersion-free (static) and also frequencydependent (dynamic) linear polarizabilities (α) and second hyperpolarizabilities (γ) at λ = 825-1125 nm and 1050-1600 nm wavelength areas using the time-dependent Hartree-Fock (TDHF) method. The ab-initio calculation results with non-zero values on (hyper)polarizabilities indicate that the synthesized molecule might possess microscopic third-order NLO phenomena. © World Scientific Publishing Company.