Solubility and solvation interaction in neat and mixed binary solvents

Solubilities of 1-ethyl-4-cyanopyridinium iodide and two ketocyanine dyes h ave been determined in various neat and mixed binary solvents. A multiple l inear regression analysis for neat solvents indicates that the solubility d epends on various modes of solute-solvent interaction and also an the Hilde brand solubility parameter representing the cohesive energy density of the solvent. Data in mixed binary solvents point to a deviation from ideal solu tion behaviour. The results have been explained in terms of solvent-solvent interaction as well as a difference in solute-solvent interaction for the component solvents.