Deposition of Rhodamine B dye on flexible substrates for flexible organic electronic and optoelectronic: Optical spectroscopy by Kramers-Kronig analysis

Rhodamine B (RhB) films prepared via spin coater on polyacetate flexible substrates. The X-ray diffraction spectroscopy has been done for RhB/polyacetate flexible substrate and displays an amorphous structure of RhB films in the various thicknesses in the range of 74-303 nm. K-K relations used for determining the refractive index and exhibits a normal dispersion at lambda > 600 nm and an anomalous dispersion at lambda < 600 nm. The electronic transitions reveal two bands of absorbance Q band which due to the first pi ->pi* transitions and Soret band due to the second pi ->pi* transitions. Also, other linear optical constant such as absorption coefficient, band energy gap, dielectric constants, and optical conductivity were discussed. On the other hand, the first (chi((1))) and third (chi((3))) orders of nonlinear optical susceptibilities as well as a nonlinear refractive index (n(2)) were calculated and discussed. The electrical and optical conductivities demonstrated the high absorption of RhB/flexible substrates inferring the chance of utilizing these films as optoelectronic gadgets.