Nonlinear optical study of 1,1'-methylenedipyridinium bis[tetrachloride gold(III)] hybrid salt

The third-order nonlinear optical properties of 1,1'-methylenedipyridinium bis[tetrachloride gold(III)] were investigated by the z-scan method using CW diode laser. The experimental results led to estimation of the nonlinear optical absorption coefficient (β), the nonlinear optical refraction (n₂), and third-order nonlinear optical susceptibility (χ³). Our results show that the excited-state absorption cross-sections (σ_{ex}) is larger than the ground-state absorption cross-sections (σ_{g}), this suggests that the nonlinear optical absorption in the MPTC gold(III) is due to the reverse saturable absorption mechanism. Furthermore, the obtained results suggest that our material is considered as a promising candidate for future optical devices applications