Synthesis and third-order nonlinear optical properties of a sandwich-type mixed (phthalocyaninato)(schiff-base) triple-decker complexes

• First investigation on nonlinear optical properties of mixed sandwich-type complexes.
• Nonlinearity parameters were evaluated from experimental data.
• Large nonlinear optical susceptibility.

A novel sandwich-type erbium triple-decker complexes with mixed phthalocyanine and Schiff-base ligands was synthesized and characterized by optical absorption spectroscopy. The third-order nonlinear optical properties of the sandwich-type complexes in dichloromethane were investigated using Z-scan measurement at 532 nm with 20 ps pulses. The Z-scan results reveal that the sandwich-type complexes exhibit strong reverse saturable absorption and self-focusing effect. The third-order nonlinear susceptibility and second-order hyperpolarizability of the complexes are estimated to be 7.31 × 10−13 esu and 0.94 × 10−30 esu, respectively. Our results indicate that the sandwich-type mixed (phthalocyaninato)(Schiff-base) complexes are promising candidate materials for future nonlinear optical applications such as wavelength conversion and optical switching.