The optical activity of dye molecules in different environments is of great interest for many applications such as laser system or biological imaging. We investigate the fluorescence and absorption spectrum of nano-confined Xanthene dyes (Rhodamine B and Fluorescein sodium salt) in a two-phase liquid. Each shows very distinct optical behavior in the water phase of a reverse microemulsion. Their optical properties such as absorption and fluorescence for different dye and nanodroplets concentration are investigated. We show that for the same concentration of dye in the microemulsion the peak of fluorescence intensity is varied by altering the concentration of nanodroplets. However, the trend of the change is widely different depending on the hydrophobicity of dyes. Quantum–mechanical second order perturbation theory is used to calculate the ratio of dipole moments in the ground and exacted states, which accounts for Stokes shift of fluorescence peak. Photon correlation spectroscopy is employed to check the trace of dye in the oil phase of the microemulsion

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