Refractive index and urbach tail of 2,7dichlorofluorecsien(DCF)‎ dye

Abstract EN

2,7 Dichlorofluorecsien (DCF) dye thin films are deposited on glass substrates by spin coating.

In this study the optical properties of the thin films were studied.

The reflectance and transmittance spectrophotometric measurements have been done in the spectral range from 300nm to 800nm.

The transmittance of the prepared thin films is 96 % in the long wavelength > 550nm and the reflectance is 9 %.

Determination of the optical constants such as refractive index(n=1.65), absorption coefficient(∝),optical energy gap (Eg=2.18e V) ,Urbach tail(∆Et=0.135e V) and dielectric constant in real and imaginary parts(ε1,ε2) in this wavelength range has been evaluated.

Optical and electrical conductivities (αopt , ∝e ) of the films have been done.

Further, normal dispersion of the refractive index has been analyzed in terms of single oscillator model of free carrier absorption to estimate the dispersion and oscillation energy.