Synthesis, structure and third-order non-linear optical properties of W/S cluster [Fe(DMF)6][W2(μ2-S)2S4]

The homometal cluster [Fe(DMF)6][W2(μ2-S)2S4] 1 (DMF = dimethylformamide) was successfully synthesized by low-temperature solid-state reactions. X-ray single-crystal diffraction studies reveal that compound 1 is dinuclear anion cluster. The compound was characterized by elemental analyses, IR spectra and UV–vis spectra. The third-order non-linear optical (NLO) properties of the cluster were also investigated and exhibited non-linear rare saturation absorption (α2 < 0) and self-defocusing performance with modulus of the hyperpolarizabilities 9.547 × 10−31 esu for 1.