Refractive Index Deviations Research Articles

Densities, Refractive Indices and Excess Properties of Binary Mixtures of Acetonitrile with Benzene, Toluene, m-Xylene and Mesitylene at Temperatures from (298.15 to 313.15) K

The densities ( ρ) and refractive indices ( n D) of binary mixtures of acetonitrile with benzene, toluene, m-xylene and mesitylene including those of pure liquids, over the entire composition range expressed by mole fraction x 1 of acetonitrile were measured at temperatures (298.15, 303.15, 308.15, and 313.15) K under atmospheric pressure. From the experimental data, the excess molar volumes ( E m V ) and the deviations in refractive indices (Δn) were calculated. These results are fit to a Redlich -Kister type polynomial equation. The results indicate the presence of weak interactions between acetonitrile and aromatic hydrocarbon molecules. The deviations in E m V values follow the order toluene < benzene < m-xylene < mesitylene. The results are discussed in terms of the intermolecular interactions.

Densities, Excess Molar Volumes, and Refractive Properties of the Binary Mixtures of the Amino Acid Ionic Liquid [bmim][Gly] with 1-Butanol or Isopropanol at T = (298.15 to 313.15) K

Densities and refractive indices were determined for two ionic liquid (IL) mixtures formed by 1-butyl-3-methylimidazolium glycine acid salt ([bmim][Gly]), with 1-butanol or isopropanol, respectively, over the mole fraction range from (0.1 to 0.9) and at temperatures from (298.15 to 313.15) K at intervals of 5 K and atmospheric pressure. Excess molar volumes and refractive index deviations have been calculated from the experimental data and fitted to a Redlich–Kister polynomial function. The excess volumes for the two systems are negative over both the composition and temperature ranges, whereas the refractive index deviations are always positive. Finally, results have been interpreted in terms of molecular interactions and molecular structures in these binary mixtures.

Densities, Viscosities, and Refractive Properties of the Binary Mixtures of the Amino Acid Ionic Liquid [bmim][Ala] with Methanol or Benzylalcohol at T = (298.15 to 313.15) K

Densities, viscosities, and refractive indices were determined for two ionic liquid (IL) mixtures formed by 1-butyl-3-methylimidazolium alanine acid salt ([bmim][Ala]) with methanol or benzylalcohol, respectively, over the mole fraction range from (0.1 to 0.9) and at temperatures from (298.15 to 313.15) K at intervals of 5 K and atmospheric pressure. Excess molar volumes, viscosity deviations, and refractive index deviations have been calculated from the experimental data and fitted to a Redlich–Kister polynomial function. The results have been interpreted in terms of ion–dipole interactions and structural factors of the IL and alcohol molecular liquids.

Effect of Temperature on the Physico-Chemical Properties of a Room Temperature Ionic Liquid (1-Methyl-3-pentylimidazolium Hexafluorophosphate) with Polyethylene Glycol Oligomer

A systematic study of the effect of composition on the thermo-physical properties of the binary mixtures of 1-methyl-3-pentyl imidazolium hexafluorophosphate [MPI][PF6] with poly(ethylene glycol) (PEG) [Mw = 400] is presented. The excess molar volume, refractive index deviation, viscosity deviation, and surface tension deviation values were calculated from these experimental density, ρ, refractive index, n, viscosity, η, and surface tension, γ, over the whole concentration range, respectively. The excess molar volumes are negative and continue to become increasingly negative with increasing temperature; whereas the viscosity and surface tension deviation are negative and become less negative with increasing temperature. The surface thermodynamic functions, such as surface entropy, enthalpy, as well as standard molar entropy, Parachor, and molar enthalpy of vaporization for pure ionic liquid, have been derived from the temperature dependence of the surface tension values.

Investigation on viscous synergism and antagonism prevailing in binary mixtures of cyclohexylamine with isomeric butanols by volumetric, viscometric, refractive index and ultrasonic speed measurements

Densities, ρ, viscosities, η, speeds of sound, u and refractive indices, n D, were measured for the binary systems of cyclohexylamine with 1-butanol, 2-butanol, isobutanol and t-butanol at 298.15 K over the entire composition range. From the experimental results, the excess volume, V E, the deviations in relative viscosity, Δη, and synergic index, I S, are derived by the equation developed by Kalentunc-Gencer and Peleg [J. Texture Studies 17, 61 (1986)] and Howell [Elucidation of protein–protein interactions in gels and foams, in Proceedings of 7th International Conference Wales 1993, edited by G.O. Phillips, P.A. Williams and D.J. Wedlock (Oxford University Press, New York, 1994)], respectively. Isentropic compressibility, , and deviation in refractive indices, Δn D, were also calculated. The above functions show the deviations from the additivity law, which depend on the nature of the carbon chain of the alcohols.

Densities, refractive indices and excess molar volumes for binary mixtures of protic ionic liquids with methanol at T = 293.15 to 313.15 K

Densities and refractive indices for the binary mixtures involving four different Protic Ionic Liquids (PILs) namely (2-Hydroxyethanaminium formate [HEF] + methanol), (2-Hydroxyethanaminium acetate [HEA] + methanol), (2-Hydroxyethanaminium propionate [HEP] + methanol), and (2-Hydroxyethanaminium lactate [HEL] + methanol) have been measured at the temperature range from 293.15 to 313.15 K and at atmospheric pressure. The excess molar volumes V E , refractive index deviations Δ n D for these binary mixtures were calculated and correlated using Redlich–Kister equation. The coefficients of thermal expansion α, were also calculated from these experimental data. The values of V E are negative for the entire mole fraction range covered for all these binary mixtures and increased with temperature, whereas the values of Δ n D are positive and also increased with temperature. The measured refractive indices were compared with those predicted using the Lorentz–Lorenz, Gladstone–Dale, and Eykman equations and a satisfactory agreement was found for all the binary systems (PILs + methanol) studied in the present work.

Viscosities, densities, speeds of sound and refractive indices of binary mixtures of o-xylene, m-xylene, p-xylene, ethylbenzene and mesitylene with 1-decanol at 298.15 and 308.15 K

The viscosities η, densities ρ, speeds of sound u and refractive indices n D of binary mixtures of 1-decanol with o-xylene, m-xylene, p-xylene, ethylbenzene and mesitylene have been measured over the entire range of composition at 298.15 and 308.15 K and at atmospheric pressure. Excess molar volumes V E , deviations of isentropic compressibilities Δκ, deviations of the speeds of sound ∆u, viscosity deviations Δη, excess free energies of activation for viscous flow ΔG * E and deviations of refractive indices ∆n D have been calculated from the density ρ, speed of sound u, viscosity η and refractive index n D data. The calculated excess and deviation functions have been fitted to the Redlich–Kister polynomial equations and the results analyzed in terms of molecular interactions and structural effects. The viscosity data have been correlated using McAllister's three body interaction model at different temperatures.

Phase Behaviour of 1‐Ethyl‐3‐methylimidazolium Thiocyanate Ionic Liquid with Catalytic Deactivated Compounds and Water at Several Temperatures: Experiments and Theoretical Predictions

Density, surface tension and refractive index were determined for the binary mixture of catalytic deactivated compounds with 1‐ethyl‐3‐methylimidazolium thiocyanate {[EMIM][SCN]} at temperature of (298.15 to 323.15) K. For all the compounds with ILs, the densities varied linearly in the entire mole fraction with increasing temperature. From the obtained data, the excess molar volume and deviation of surface tension and refractive index have been calculated. A strong interaction was found between similar (cation‐thiophene or cation‐pyrrole) compounds. The interaction of IL with dissimilar compounds such as indoline and quinoline and other multiple ring compounds was found to strongly depend on the composition of IL at any temperatures. For the mixtures, the surface tension decreases in the order of: thiophene &gt; quinoline &gt; pyridine &gt; indoline &gt; pyrrole &gt; water. In general from the excess volume studies, the IL‐sulphur/nitrogen mixture has stronger interaction as compared to IL‐IL, thiophene‐thiophene or pyrrole‐pyrrole interaction. The deviation of surface tension was found to be inversely proportional to deviation of refractive index. The quantum chemical based COSMO‐RS was used to predict the non‐ideal liquid phase activity coefficient for all mixtures. It indicated an inverse relation between activity coefficient and excess molar volumes.

Multistep ion exchange processes of gradient refractive index rod lens

A mathematical model for research on the refractive index profile (RIP) of multistep ion exchange processes (IEPs) of gradient refractive index rod lenses (GRINs) is established by the different initial condition and boundary condition, based on the Fickian diffusion equation. GRIN rod lenses have been fabricated using the three-step IEPs. Research results indicate that the experimental deviations of refractive index (DRI) are in good agreement with the theoretical data. The DRI of three-step IEPs is superior to the one- and two-step IEPs and smaller than 10(-5).

Thermophysical properties of {(±)-linalool + propan-1-ol}: A first stage towards the development of a green process

In this paper, densities, speeds of sound and refractive indexes of binary mixture of {(±)-linalool (1) + propan-1-ol (2)} at four temperatures (283.15, 298.15, 313.15, and 328.15) K and 0.1 MPa are reported over the whole composition range. These data were used to calculate excess molar volume, speed of sound deviation, excess isentropic compressibility, refractive index deviation, molar refraction, and molar refraction deviation at the four work temperatures. All magnitudes were fitted to the Redlich–Kister equation. Subsequently prediction of speed of sound and refractive index was carried out using several theoretical models or equations. On the other hand, the density of the same mixture was determined in the same temperature range at pressures from 20 MPa to 40 MPa. Four equation of state (Peng–Robinson, Patel–Teja, SAFT, PC-SAFT) were tested as predictive models of the PρT behavior. The best results were obtained by PC-SAFT, with an average absolute deviation of 0.83%.

Volumetric Properties, Viscosities, and Refractive Indices for Aqueous 1-Amino-2-Propanol (Monoisopropanolamine (MIPA)) Solutions from (298.15 to 343.15) K

Densities and viscosities at six temperatures in the range (298.15 to 343.15) K and refractive indices at nine temperatures in the range (293.15 to 333.15) K are reported for aqueous solutions of 1-amino-2-propanol (monoisopropanolamine (MIPA) or 1-AP). Excess molar volumes, viscosity deviations, and refractive index deviations were calculated from the measurement results and correlated as a function of composition using the Redlich-Kister relation and polynomial equations. Partial molar volumes at infinite dilution were determined from the apparent molar volumes. Negative values for excess molar volumes and molar refraction changes are observed over the whole composition range, whereas viscosity data exhibit both negative and positive deviations. Cross-associated hydrogen bonds forming between 1-AP and water contribute to the deviations in the properties with respect to mole fractions and temperatures.

Volumetric, Acoustic, and Refractive Properties of Isomeric Chlorobutanes with Diisopropyl Ether

From experimental data (densities, speeds of sound, and refractive indices) over the temperature range (283.15 to 313.15) K for the binary mixtures formed by an isomer of chlorobutane (1-chlorobutane, 2-chlorobutane, 2-methyl-1-chloropropane, or 2-methyl-2-chloropropane) plus diisopropyl ether, the following properties have been calculated: excess volumes, excess isentropic compressibilities, and refractive index deviations. The excess properties and deviations were fitted using the Redlich-Kister polynomial equation. The excess volumes and excess isentropic compressibilities for the four systems are all negative over both the composition and temperature ranges, whereas the refractive index deviations are always positive.

Densities, viscosities, refractive indices, and surface tensions for binary and ternary mixtures of 2-propanol, tetrahydropyran, and 2,2,4-trimethylpentane

Densities, viscosities, refractive indices, and surface tensions of the ternary system (2-propanol + tetrahydropyran + 2,2,4-trimethylpentane) at T = 303.15 K and its constituent binary systems (2-propanol + tetrahydropyran, 2-propanol + 2,2,4-trimethylpentane, and tetrahydropyran + 2,2,4-trimethylpentane) at T = (293.15, 303.15, 313.15, and 323.15) K were measured at atmospheric pressure. Densities were determined using a vibrating-tube densimeter. Viscosities were measured with an automatic microviscometer based on the rolling-ball principle. Refractive indexes were measured using a digital Abbe-type refractometer. Surface tensions were determined by the Wilhelmy-plate method. From these data, excess molar volumes, deviations in viscosity, deviations in refractive index, and deviations in surface tension were calculated. The results for the binary and ternary systems were fitted to the Redlich–Kister equation and the variable-degree polynomials in terms of compositions, respectively. The experimental and calculated quantities are used to study the nature of mixing behaviour between mixture components.

Excess properties of binary mixtures hexane, heptane, octane and nonane with benzene, toluene and ethylbenzene at T = 283.15 and 298.15 K

Densities, speeds of sound and the refractive indices of binary systems containing alkanes (hexane, heptane, octane and nonane) with aromatic compounds (benzene, toluene and ethylbenzene) at T = 283.15 and 298.15 K under atmospheric pressure were determined over the whole composition range. From the experimental results, the derived and excess properties (excess molar volumes, isentropic compressibility, excess molar isentropic compressibility and refractive index deviations) at T = 283.15 and 298.15 K were calculated and satisfactorily fitted to the Redlich–Kister equation.

Density, Speed of Sound, and Refractive Index of Aqueous Binary Mixtures of Some Glycol Ethers at T = 298.15 K

The experimental data of densities (ρ), speeds of sound (u), and refractive indices (nD) of aqueous solutions of different glycol ethers, namely, ethylene glycol iso-propyl ether (EGIPE), ethylene glycol monobutyl ether (EGMBE), diethylene glycol dimethyl ether (DEGDME), diethylene glycol monobutyl ether (DEGMBE), propylene glycol monomethyl ether (PGMME), and dipropylene glycol monomethyl ether (DPGMME), over the entire composition range, at temperature T = 298.15 K, and at one atmospheric pressure have been obtained. The derived parameters such as the apparent molar volume (ϕV) of solute, isentropic compressibility of solution (βS), apparent molar isentropic compressibility (ϕKS) of solute, excess molar volume (VE) of solution, molar refraction ([R]1,2), deviation in refractive index (ΔnD) of solutions, deviation in molar refraction (Δ[R]1,2), and the deviation in isentropic compressibility (ΔβS) have been computed. The limiting apparent molar volumes of solutes (ϕV0), limiting apparent molar isentropic...

Densities, Viscosities, and Refractive Indices of Binary Mixtures of Methyl Ethyl Ketone + Pentanol Isomers at Different Temperatures

Densities, viscosities, and refractive indices of mixing of methyl ethyl ketone with 1-pentanol, 2-pentanol, and 3-pentanol have been measured as a function of composition range at temperatures (298.15, 308.15, and 318.15) K and ambient pressure. Excess molar volumes VmE, viscosity deviations Δη, and refractive index deviations ΔnD were calculated and correlated by the Redlich−Kister-type function to derive the coefficients and estimate the standard error. From the experimental data, partial molar volumes, Vm,i, and partial molar volumes at infinite dilution, Vm,i0, were also calculated. The latter values are interesting from a theoretical point of view since at infinite dilution the only interactions present are solute−solvent interactions. The effect of temperature and −OH group position of pentanol isomers on the excess molar volumes, viscosity, and refractive index deviations of its mixtures with methyl ethyl ketone is discussed in terms of the nature and type of intermolecular interactions in binar...

Phase equilibrium and thermophysical properties of mixtures containing a cyclic ether and 1-chloropropane

The phase equilibrium, at T = 298.15 and 313.15 K and several thermophysical properties (density, sound velocity, refractive index) at T = 283.15, 298.15 and 313.5 K of mixtures formed by a cyclic ether (tetrahydropyran, tetrahydrofuran) and 1-chloropropane has been studied. Excess Gibbs functions, excess volumes, excess isentropic compressibilities and refractive index deviations have been obtained from the experimental data. Both the molecular characteristics of the pure compounds and the molecular interactions in the mixing process have been used to analyse the results. The SAFT-VR approach has been applied without adjustable parameter to predict the phase behaviour at isothermal conditions of the mixtures. Results have been analysed and compared to those obtained in previous studies.

Excess thermodynamic properties of binary mixtures of ionic liquid (1-butyl-3-methylimidazolium hexafluorophosphate) with alkoxyalkanols at several temperatures

Physical properties such as densities, ρ, speed of sound, u, and refractive indices, n, have been measured for the binary mixtures of ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate, [bmim][PF 6] with diethylene glycol monomethyl ether (DEGMME), propylene glycol monomethyl ether (PGMME) and propylene glycol monoethyl ether (PGMEE) over the whole composition range at atmospheric pressure. Experimental densities have been used to estimate excess molar volume V m E. Changes in isentropic compressibility, Δ κ S , have been estimated by using experimental speed of sound and density values. Experimental refractive indices values have been used to calculate the deviation in refractive indices, Δ φ n, and molar refraction, Δ x R. Excess properties are fitted to the Redlich–Kister polynomial equation to obtain the binary coefficients and the standard errors. Apparent molar volume and apparent molar compressibility at infinite dilution, V φ, i ∞ and K φ, i 0 have been calculated to gain information about solute–solvent interactions. The results are compared with our earlier studies concerning the binary mixtures of [bmim][PF 6] with alkoxyethanol or poly ethers.

&lt;b&gt;Molecular interactions with reference to manifestation of solvation effects in binary mixtures of ethyl acetoacetate with some methane derivatives by physicochemical techniques&lt;/b&gt;

Density, &rho;, viscosity, &eta;, speed of sound, u, and refractive index, nD, were measured for the binary systems of ethyl acetoacetate with dichloromethane, chloroform, carbon tetrachloride, nitromethane, methyl acetate, acetonitrile and acetic acid at 298.15 K over the entire composition range. From the experimental results, the excess molar volume, VE and the deviation in viscosity, &Delta;&eta;, were calculated. Isentropic compressibility, kSE, and deviation in molar refractive index, &Delta;R, were also calculated. These results were fitted to Redlich-Kister polynomial equation. The density and viscosity data were analyzed by some semi-empirical viscosity models, and the results have been discussed in terms of molecular interactions and structural effects. The excess properties were found to be either negative or positive depending on the molecular interactions and the nature of liquid mixtures. To explore the nature of the interactions, various thermodynamic parameters (e.g., intermolecular free length, specific acoustic impedance, etc.) have also been derived from the density and ultrasonic speed data.KEY WORDS: Density, Viscosity, Speed of sound, Isentropic compressibility, Molar refractive index, Ethyl acetoacetateBull. Chem. Soc. Ethiop. 2010, 24(1), 103-114.

Excess molar volumes and deviations of refractive indices at 298.15K for binary and ternary mixtures with pyridine or aniline or quinoline

Abstract Excess molar volume (VE) at 298.15 K are reported for the binary systems of heterocyclic nitric compounds: {ethanol + pyridine}, {ethanol + aniline}, {ethanol + quinoline}, {pyridine + aniline}, {pyridine + quinoline}, {aniline + quinoline}, {N-methylformamide (NMF) + pyridine}, {NMF + aniline}, {NMF + quinoline}, {N,N-dimethylformamide (DMF) + pyridine}, {DMF + aniline} and {DMF + quinoline}. The deviations in molar refractivity (ΔR) at 298.15 K are also reported for binary systems: {ethanol + pyridine}, {ethanol + aniline}, {NMF + pyridine}, {NMF + aniline}, {DMF + pyridine}, {DMF + aniline} and {pyridine + aniline}. The determined VE and ΔR were correlated with the Redlich–Kister equation. In addition, the ternary VE data at 298.15 K were predicted with correlated binary parameters for the systems: {ethanol + pyridine + aniline}, {ethanol + pyridine + quinoline}, {ethanol + aniline + quinoline}, {NMF + pyridine + aniline}, {NMF + pyridine + quinoline}, {NMF + aniline + quinoline}, {DMF + pyridine + aniline}, {DMF + pyridine + quinoline} and {DMF + aniline + quinoline}. The ternary ΔR data at 298.15 K are also predicted for the systems: {ethanol + pyridine + aniline}, {NMF+ pyridine + aniline} and {DMF + pyridine + aniline}.