Alcoholic Compounds–Physical Properties and Classification Categories, Including Monohydric, Dihydric, Polyhydric and Carbohydrate Derivatives

The refractive index, static electric constant, and E _T(30) polarity of monohydric and polyhydric alcohols, as well as carbohydrates, are determined by the complex interplay between the concentrations of CH and COH bonds. Correlation of the refractive index of carbohydrates as a function of the molar concentration of the constituting CH bonds, N_CH.

The relationships between molar mass (M), density (ρ), relative static permittivity (ε _r), and refractive index (nD20$n_{\text{D}}^{20}$) of alcohol derivatives are investigated. It is important to determine the partial molar concentration of hydroxyl groups (N _OH) and the partial molar concentration of CH bonds (N _CH) and their effect on the physical properties of ε _r and nD20$n_{\text{D}}^{20}$ with reference to the Clausius–Mossotti and Lorentz–Lorenz relationships. Unlike ε _r, the nD20$n_{\text{D}}^{20}$ is a crucial physical criterion for the reliability of the approach. Individual correlations of nD20$n_{\text{D}}^{20}$ with N _CH or N _OH are recognized for mono-, di-, tri-, tetra-, and polyhydric alcohol derivatives and carbohydrates. When the number of OH groups per molecule exceeds four, nonlinear effects come into play, probably due to polarization effects of the OH group network. The nD20$n_{\text{D}}^{20}$ of carbohydrates is largely determined by the N _CH value. Relationships of the empirical E _T(30) polarity parameter of polyhydric alcohols, aqueous carbohydrate solutions, solvent mixtures, and polymers ε _r are demonstrated.

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