In this work, chlorophyll b is subjected to encapsulation through an emulsion system consisting of a bi-immiscible liquid phase system where water D2O and n-heptane are separated through AOT surfactant stabilization. The nonlinear optical properties of chlorophyll encapsulated are investigated along with its behavior in ionic solutions under different pHs using Z-scan techniques employing a diode laser (λ=532 nm). Chlorophyll b shows dual absorbance peaks at 630 and 410 nm (1.8 eV bandgap). Encapsulation increased its fluorescence and Rayleigh scattering/absorbance ratio due to enhanced polarizability. Encapsulation increased nonlinear absorption coefficient value by 10 times compared to the D2O solution, primarily due to alterations in polarizability effects. Given that encapsulation reduces the dielectric constant of the medium, the role of different solvents is investigated. Density functional theory simulation indicated the solvent dielectric constant greatly affected the molecular dipole moment and polarizability. The present study points toward a significant role of encapsulation over regulating the nonlinear optical and electronic properties of chlorophyll b, thus proving to be interesting for its utilization in advanced optical technologies.

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