Optical Functions of Methanol and Ethanol in Wide Spectral Range

The motivation of this paper is to determinate the precise complex refractive indices dispersion of ethanol, methanol, and their solutions in the wide spectral range from 8 to 40 000 cm⁻¹ (wavelength range from 250 nm to 1.25 mm) in coupling to biosensors applications (body liquids analyses, tissue ethanol solutions testing, etc.) because a specification of the complex optical functions consistent with Kramers–Kronig dispersion relations in the whole mentioned spectral range was still missing. A general method combining UV/visible/near-infrared spectroscopy and Mueller matrix ellipsometry, Fourier transform infrared spectroscopy (FTIR), infrared attenuated total reflection (ATR) spectroscopy, and terahertz time-domain spectroscopy (THz-TDS) is proposed. The experimental data are modeled using a dielectric function parametrization based on the Brendel–Bormann oscillators.