Spectral and Thermodynamical Studies on iso-Quinolinium Carbethoxy Methylid (iQCEM) Solutions with Binary Solvent Water (W) + Ethanol (E)

The electronic absorption spectra of iso-Quinolinium Carbethoxy Methylid (iQCEM) in binary solvents water + ethanol in twenty two different ratios were analyzed in order to obtain information about the water content in the first solvation shell of iQCEM in the studied ternary solutions. The main result of this investigation is given by the approximately equal values found for water molar fraction in the all ternary solutions and water average statistic weight in the first solvation shell of iQCEM for all water+ ethanol binary solvents. Also the estimation of the excited state dipole moment was carried out based on the molecular modelling results and the solute molecule solvatochromic behaviour.