Temperature Dependence of Changes of Refractive Index in Methyl Acetate,Ethanol and 2-Propanol Mixtures

Abstract

The refractive indices of the mixtures methyl acetate+ethanol+2-propanol, methyl acetate+ethanol and methyl acetate+2-propanol have been determined experimentally as a function of composition at the temperature range 288.15–308.15K and atmosphere. Parameters of polynomial equations which represent the composition and temperature dependence of the corresponding derived magnitude are gathered. The applicability of semiempirical equations is analyzed in order to estimate the ternary changes of refractive indices on mixing at these temperatures by means of only binary derived values.     

Changes of refractive indices of the ternary mixtures chlorobenzene + n-hexane + (n-nonane or n-decane) at 298.15 K

The measures of the refractive indices of the ternary mixtures chlorobenzene + n-hexane + (n-nonane or n-decane) have been done at 298.15?K and atmospheric pressure in the whole composition diagram. The composition dependence of the derived magnitude has been compared with the data obtained with several theoretical models. Attending to the accurate results of these models, the equation of state enclosing mixing rules are pointed out as simple procedures for a multicomponent estimation of refractive indices, the corresponding binary parameters could be used to other thermophysical studies.     

Densities,speeds of sound and refractive indices for binary and ternary mixtures of {diethylcarbonate (1) + p-chloroacetophenone (2) + 1-hexanol (3)} at 303.15 K for the liquid region and at ambient pressure

Densities (ρ), speeds of sound (u) and refractive indices (n_D ), of the ternary mixture (diethylcarbonate + p-chloroacetophenone + 1-hexanol) and the involved binary mixtures (diethylcarbonate + p-chloroacetophenone, diethylcarbonate + 1-hexanol, and p-chloroacetophenone + 1-hexanol) have been measured over the whole composition range at 303.15 K for the liquid region and at ambient pressure. The data obtained are used to calculate isentropic compressibilities k_s , isentropic compressibility deviations Δk_s and refractive index deviations Δn_D , of the binary and ternary mixtures. The data of isentropic compressibility deviations and refractive index deviations of the binary systems were fitted to the Redlich–Kister equation while the best correlation method for the ternary system was found using the Cibulka equation. The experimental data of the constitute binaries and ternaries are analysed to discuss the nature and strength of intermolecular interactions in these mixtures.     

Densities,refractive indices,and derived excess properties of the binary systems tert-butyl alcohol+toluene, +methylcyclohexane,and +isooctane and toluene+methylcyclohexane,and the ternary system tert-butyl alcohol+toluene+methylcyclohexane at 298.15 K

This paper reports experimental densities and refractive indices of the binary systems tert-butyl alcohol (TBA)+toluene, +isooctane, and +methylcyclohexane, and toluene+methylcyclohexane, and the ternary system TBA+toluene+methylcyclohexane, over the entire range of composition at 298.15 K. Excess molar volumes and changes of refractive indices were evaluated from the experimental data obtained. These derived properties were fitted to variable-degree polynomials. The experimental values of physical properties were compared with the values estimated by different methods of prediction.     

Prediction of Excess Volumes and Excess Surface Tensions from Experimental Refractive Indices

Abstract

Refractive indices for the binary liquid mixtures: {hexane or heptane + ethanol}, {o-xylene + benzene} and {cyclohexane + benzene, toluene or hexane} were measured at 298.15 K. Excess refractive indices were calculated and fitted to a Redlich-Kister function. Using some mixture rules (Lorentz-Lorenz, Dale -Gladstone, Eykman, Oster, Arago-Biot and Newton), predictions for v^E have been made and compared with experimental data taken from the literature. Furthermore the Sugden equation has been used in two different ways for predicting excess surface tensions: the first one starting from densities and the other one from refractive indices. Results are plotted together with the literature data.     

Density,viscosity and refractive index for ethyl tert -butyl ether + 2-butoxyethanol mixtures

Densities (ρ) at 293.15, 298.15, 303.15, 308.15, and 313.15 K, viscosities (η) at 293.15, 298.15, and 303.15 K and refractive indexes (n) at 298.15 K of binary mixtures of ethyl tert-butyl ether (1) + 2-butoxyethanol (2), are reported. The excess molar volumes (V ^E) and the viscosities, and refractive index deviations (Δln η and Δn) were calculated from these experimental data. The results are discussed in terms of intermolecular interactions.     

Refractive Indices, Densities and Excess Molar Volumes of Monoalcohols + Water

The refractive index, n _D , and density, ρ, of binary mixtures of monoalcohols + water, have been measured at a temperature of 298.15,K and atmospheric pressure. The variation of the refractive indices of these solutions has also been determined with temperature in the range T = (278.15 to 338.15) K and atmospheric pressure. A comparative study has been made of the refractive indices obtained experimentally and those calculated by means of the Lorentz-Lorenz [Theory of Electrons, Dover Phoenix (1952)] and Gladstone-Dale relations [Trans. R. Soc. London 148:887–902 (1858)]; in all cases, the Gladstone–Dale equation was seen to afford values similar to those obtained experimentally. Calculations have been made of the excess molar volumes, V ^E, and the molar refraction deviations, ΔR, of these mixtures and the differences between the experimental values for refractive index and those obtained by means of the Gladstone–Dale equation. Values of V ^E were compared with others in the literature. In all cases the V ^E values were negative, and in all cases, except in the methanol + water, ΔR showed a maximum for x = 0.8.     

Refractive Indices, Viscosities, and Densities for L-Cysteine Hydrochloride Monohydrate + D-Sorbitol + Water, and Glycerol + D-Sorbitol + Water in the Temperature Range between T=303.15 K and T=323.15 K

Viscosities, refractive indices, and densities for ternary systems of (L-cysteine hydrochloride monohydrate [LCHCMH] + D-sorbitol + water) and (glycerol + D-sorbitol + water) and binary systems of ([LCHCMH] + water) and (D-sorbitol + water) have been measured at several temperatures (between T=303.15 K and T=323.15 K) and mass fractions (0.1 to 0.8) at atmospheric pressure. For these mixtures, the experimental values of density were correlated with an experimental equation and the experimental values of viscosity were correlated with the Jones-Dole equation.     

Anomalous density and refractive index variation of a nematic liquid crystal

Abstract

This paper reports the results of the measurement of refractive indices and densities of p-ethoxyphenyl trans-4-butyl cyclohexane carboxylate at different temperatures. The molecular polarizabilities have been calculated from refractive indices using Vuks' formula and orientational order parameters are determined from the polarizability values. The order parameter values have been compared with those obtained from Maier-Saupe theory. The compound shows anomalous behaviour regarding variation of density, ordinary refractive index and order parameter values with temperature. This is consistent with our previous X-ray study of this compound. The possible reason for this peculiar behaviour has been discussed.     

Excess Volume of Ternary Water + Diacetone Alcohol + 2-Propanol as a Function of Pressure,Temperature and Composition

Abstract

The excess volume V^E of the ternary water + diacetone alcohol (or DAA) + 2-propanol and of the three binaries water + DAA, water + 2-propanol and DAA + 2-propanol was evaluated from experimental density data (2772 values) as a function of the pressure P (between 0.1 MPa and 65 MPa), the temperature T (303.15K, 323.15K and 343.15K) and the composition. Various representative models are discussed. It is possible to account for the values of the density with an average absolute deviation of about 0.06% in the experimental P-T domain.     

Excess Volumes of Binary Mixtures of Benzene + 1-Alkanols at 303.15 K

Abstract

Excess molar volumes V^E of binary mixtures of benzene + 1-propanol, + 1-butanol, + 1-pentanol, + 1-hexanol, + 1-heptanol, + 1-octanol, + 1-nonanol and 1-decanol were measured at 303.15 K. The V^E values are positive over the entire range of composition for these mixtures. The results are discussed in terms of intermolecular interactions.     

Refractive Index of Liquid Mixtures: Theory and Experiment

An innovative approach is presented to interpret the refractive index of binary liquid mixtures. The concept of refractive index “before mixing” is introduced and shown to be given by the volume‐fraction mixing rule of the pure‐component refractive indices (Arago–Biot formula). The refractive index of thermodynamically ideal liquid mixtures is demonstrated to be given by the volume‐fraction mixing rule of the pure‐component squared refractive indices (Newton formula). This theoretical formulation entails a positive change of refractive index upon ideal mixing, which is interpreted in terms of dissimilar London dispersion forces centred in the dissimilar molecules making up the mixture. For real liquid mixtures, the refractive index of mixing and the excess refractive index are introduced in a thermodynamic manner. Examples of mixtures are cited for which excess refractive indices and excess molar volumes show all of the four possible sign combinations, a fact that jeopardises the finding of a general equation linking these two excess properties. Refractive indices of 69 mixtures of water with the amphiphile (R,S)‐1‐propoxypropan‐2‐ol are reported at five temperatures in the range 283–303 K. The ideal and real refractive properties of this binary system are discussed. Pear‐shaped plots of excess refractive indices against excess molar volumes show that extreme positive values of excess refractive index occur at a substantially lower mole fraction of the amphiphile than extreme negative values of excess molar volume. Analysis of these plots provides insights into the mixing schemes that occur in different composition segments. A nearly linear variation is found when Balankina’s ratios between excess and ideal values of refractive indices are plotted against ratios between excess and ideal values of molar volumes. It is concluded that, when coupled with volumetric properties, the new thermodynamic functions defined for the analysis of refractive indices of liquid mixtures give important complementary information on the mixing process over the whole composition range.     

Relative permittivities of binary mixtures of 1-butanol + n-alkane AT 298.15 k

A previous study on the physical properties of 1-alkanol + n-alkane has establised a correlation between dielectric permittivity at 1 GHz and excess molar volumes for all binary systems that were studied. In order to determine whether this behaviour is similar at lower frequencies, relative permittivity was measured at 100 kHz. The refractive index was measured to explore the effects at higher frequencies. Mixtures under study are in particular the systems (1-butanol + n-hexane, or n-octane, or n-decane) at the temperature of 298.15 K and atmospheric pressure, over the entire composition range. This revised version was published online in July 2006 with corrections to the Cover Date.     

Low-birefringence liquid crystal mixtures for photonic liquid crystal fibres application

ABSTRACT

Series of low-birefringence liquid crystal mixtures composed of alkyl alkylbicyclohexyl carbonates and modified mixtures with other compounds have been formulated, their refractive indices and electric permittivity measured upon temperature. They exhibit the ordinary refraction index n_o lower than the refractive index of silica glass in a different range of temperature. This enables to observe in photonic liquid crystal fibres (PLCFs) a change in the light propagation mechanism from photonic band gap guiding to modified total internal reflection at different temperatures. Selected applications of PLCFs are also discussed.     

Refractive Indices of the Ternary Mixtures Butanol + <Emphasis Type="Italic">n</Emphasis>-Hexane + 1-Chlorobutane

Refractive indices for the ternary mixtures formed by each one of the isomers of butanol (1-butanol, 2-butanol, 2-methyl-1-propanol and 2-methyl-2-propanol), with n-hexane and 1-chlorobutane, have been measured at 298.15 K. From these data the refractive index deviations were calculated and fitted by Cibulka’s equation, and the refractive index deviations were related to the corresponding excess volumes of the mixtures. Furthermore, several mixing rules were used to predict both refractive indices and excess volumes of the ternary mixtures from their densities or refractive indices. Electronic Supplementary Material  The online version of this article () contains supplementary material, which is available to authorized users.     

Excess Molar Volume of 1-propanol+Aniline, +N-methylaniline, +N,N-dimethylaniline

Abstract

Densities of the systems, 1-Propanol(P)+aniline(A), 1-Propanol(P)+N-Methylaniline (NMA) and 1-Propanol(P)+N,N-Dimethylaniline(DMA) have been measured from 21°C to 50°C at an interval of 5°C. The excess molar volumes, V ^E, of the systems, P+A and P +NMA have been found to be negative for the whole range of composition. V^E of the system P+DMA has also been found to be negative, except in DMA-rich region where small positive excess volume is observed. The negative excess volume has been explained primarily in terms of strong specific interaction and size difference of unlike molecules. The magnitude of the negative excess volumes of these systems is of the order, P+A > P + NMA > P + DMA, which has been strongly influenced by steric effect due to CH₃ group attached to N-atom of NMA and DMA. In the highly rich region of DMA in P+DMA system the small positive excess volume is accounted for by the steric effect and breaking up of H-bond of 1-Propanol.     

Densities and Viscosities of the Binary Mixtures Decanol + Some n-Alkanes at 298.15 K

Abstract

Densities and viscosities of four binary liquid systems decanol +n-heptane, +n-octane, +n-nonane, +n-decane, have been determined at 298.15 K and atomospheric pressure, over the complete composition ranges. The excess values of molar volume, viscosity and Gibbs free energy for the activation of flow were evaluated. The Grunberg-Nissan parameter was also calculated. The viscosity data were fitted to the equations of McAllister and Auslander.     

Volumetric Properties and Refractive Indices for Binary Mixtures of 1-Propyronitrile-3-hexylimidazolium Bromide + Ethanol at Temperatures from 293.15 to 323.15 K

Densities and refractive indices have been measured for binary mixtures of 1-propyronitrile-3-hexylimidazolium bromide + ethanol in the temperature range 293.15–323.15 K. From the experimental data the excess molar volume V ^E, refractive index deviation Δn _D, and the coefficient of thermal expansion α were calculated and fitted to fifth- and third-order Redlich–Kister type equations, respectively. Using the measured densities, the apparent molar volumes (V _ϕ ), limiting apparent molar volumes (V_f⁰V_{\phi}^{0}) and limiting apparent molar expansivities (E_f ⁰E_{\phi} ^{0}) were also determined and the details are discussed.     

Density and Viscosity of Methanol + Trichloroethylene,n-Propanol + Trichloroethylene and n-Butanol + Trichloroethylene Mixtures

Abstract

Density and Viscosity measurements on the binary mixtures of methanol + trichloro-ethylene, n-propanol + trichloroethylene, and n-butanol + trichloroethylene binary mixtures at 303.15, 313.15 and 323.15K are reported. The representation of the data by simple mixing rules is also studied.     

Viscous synergy and antagonism,excess molar volume,isoentropic compressibility and excess molar refraction of ternary mixtures containing tetrahydrofuran,methanol and six membered cyclic compounds at 298.15 K

The densities (ρ), viscosities (η), sound speeds (u) and refractive indices (n _D) of seven ternary mixtures of cyclic ether (tetrahydrofuran), methanoland cyclic compounds; benzene, toluene, chlorobenzene, nitrobenzene, anisole, cyclohexane and cyclohexanone are determined over the entire range of composition at 298.15?K. From the experimental observations, viscosity deviation (Δη), the viscous synergy and antagonism, synergic and antagonic index are derived by the equations developed by Kalentunc-Gencer and Peleg [G. Kalentunc-Gencer and M. Peleg, J. Texture Stud. 17, 61 (1986)] and Howell [N.K. Howell, Presented at the Proceedings of the Seventh International Conference, Wales, 1993], respectively. Excess molar volume (V ^E), excess isoentropic compressibility (ΔK _S) and excess molar refraction (ΔR) have been calculated from the experimentally measured density, sound speed and refractive index values. The excess Gibb's free energy of activation (ΔG ^E) has also been calculated. The results are discussed and interpreted in terms of molecular package and specific interaction predominated by hydrogen bonding.