Ultrasonic Study of Molecular Interactions and Compressibility Behaviour of Samarium Soaps in Benzene-DMSO Mixture

Ultrasonic measurements of samarium soaps (palmitate and myristate) have been carried out in a mixture of benzene and DMSO (70%-30% v/v) to determine the critical micellar concentration(CMC), soap-solvent interaction and various acoustic parameters. The results show that ultrasonic velocity, intermolecular free length, adiabatic compressibility, adiabatic molar volume and apparent molar compressibility decrease while specific acoustic impedance, relative association and solvation number increase with increase in soap concentration. The results of ultrasonic measurements have also been explained in terms of well-known equations. Keywords: Ultrasonic measurements, molecular interactions, samarium soaps, compressibility, critical micellar concentration(CMC).

Study of nitrazepam drug interaction with alcohol: An ultrasonic and physiochemical investigation

The intermolecular interaction between the constituent components of liquid mixtures can be revealed by ultrasonic analysis. In the present study, interaction of nitrazepam drug with methyl alcohol has been studied and presented using ultrasonic tools. The investigation involves calculation of ultrasonic velocity (ν), density (ρ), viscosity (η) and the associated derived parameters. The specific acoustic impedance (Z), isentropic compressibility(β), relaxation time (τ), intermolecular free length(L_f) and solvation number Sn are calculated to reveal the interaction information. The solvent-solvent and solute-solvent interaction between the nitrazepam and alcohol molecules is considered. To see the impact of nitrazepam drug with alcohol in ordinary day to day scenario, investigation is carried out at normal temperature and pressure conditions with temperature range varying from 303K to 313K range. The results indicate increased molecule association of nitrazepam drug in presence of alcohol. This study suggests the presence of synergistic depressants effect, when nitrazepam drug is used with alcohol.

Ultrasonic Investigation of Binary Solutions of Petrolium And Its Products

<p>Experiment values of densities and ultrasonic speed of petroleum product Gasoline (Petrol) and 2T Oil were taken in different volume concentrations from 5%, 10%------, and 95% at different temperatures from 298.15K to 318.15K having difference of 5K. From the experimental data, Apparent Molar Compressibility (<em>ϕ_K</em>), Relative Association (<em>R_A</em>), Solvation Number (<em>S_n</em>), Free Energy of Activation (<em>ΔE</em>), Excess Adiabatic Compressibility (<em>β_ad^E</em>), Excess Volume (<em>V^E</em>), Excess Free Length (<em>L_f^E</em>) have been computed. These parameters are used to focus light on the nature of component molecules of binary liquids and the excess functions are found to be sensitive to the nature and extent of the intermolecular interactions taking place in these binary mixtures.</p>

Study of Molecular Interaction in Aqueous KCl at Different Temperatures

Ultrasonic velocity, density, viscosity, and electrical conductivity have been measured for an aqueous solution of KCl at different concentrations and temperatures, the frequency is maintained at a constant value. Using the above experimental data, parameters such as Rao's constant, Wada's constant, solvation number, and surface tension were calculated and the molecular interactions between molecules of KCl and water at different temperatures was studied. Using Walden's plot, the ionicity of the solution was also studied.

Investigation on Molecular Interactions of Multicharged Electrolytes Potassium Pyrophosphate and Potassium Dichromate in Aqueous D-Sorbitol Media at 298.15K by Densiometric and Acoustic Methods

Two multicharged electrolytes, potassium pyrophosphate, and potassium dichromate have been taken for densiometric and acoustic studies at 298.15K. Solvents for these electrolytes are 5, 10, and 15 weight % of D-sorbitol in water. From the density d and ultrasonic velocity U compressibility values, K_s,K_(s,ф),〖 K〗_T and W for the solutions, as well as for the solvents, are derived. Other acoustic variables like molar free volume V_f, internal pressure π_i, relative association R_A, solvation number S_n^(0 ), acoustic impedance Z are also calculated. Interpretations of these parameters in the light of molecular interactions are made. It is found that the compressibility of the solutions and the solvent decrease with a concentration of electrolyte and amount of d-sorbitol as a result of the structure breaking property of alkali metal ions and electrostriction of the solvation shells. The presence of strong ion-solvent interaction in the solution is supported by the values of the derived parameters.

Functional ionic liquids for enhancement of Li-ion transfer: the effect of cation structure on the charge–discharge performance of the Li4Ti5O12 electrode

Raman analysis revealed the following: the PP1MEM cation weakens the interaction between Li ion and TFSA anions, and thereby diminishes the solvation number of TFSA anions (NTFSA 1.56) compared with that of PP16-TFSA (NTFSA 2.40).

Ultrasonic Speed, Density, Viscosity and Associated Acoustical Parameters of Chloroform Solutions of Symmetric Double Schiff Bases at 308.15K

The density, viscosity and ultrasonic speed (2MHz) of chloroform and symmetric double Schiff bases have been investigated at 308.15K. Various acoustical parameters such as specific acoustical impedance (Z), adiabatic compressibility (Кa), Rao’s molarsound function (Rm), Vander Waals constant (b), internal pressure (π), free volume (Vf), intermolecular free path length (Lf), classical absorption coefficient (α/f2)Cl) and viscous relaxation time (τ) were determined using ultrasonic speed (U), viscosity (η) and density (ρ) data of Schiff bases solutions and correlated with concentration. Increasing linear or nonlinear trends of (Z, Rm, b, τ and (α/f2)Cl) and decreasing trend of Кa, Lf,, π and Vf with increasing concentration of Schiff bases suggested presence of strong molecular interactions in the solutions and solvophilic nature of the Schiff bases, which is further supported by the positive values of solvation number. The nature and position of substituent also affected the strength of molecular interactions.

Acoustical Studies of Some Derivatives of 1,5-Benzodiazepines at 298.15 K

Some new derivatives of 1,5-Benzodiazepines have been synthesized and their structural characterizations are done by IR, NMR and Mass Spectral data. The ultrasonic velocity, density and viscosity of these synthesized compounds have been measured in dimethyl formamide and tetrahydrofuran at 298.15 K. From these experimental data, some acoustical parameters such as isentropic compressibility, intermolecular free path length, Rao’s molar sound function, relaxation strength, solvation number etc., have been calculated which helps in understanding the molecular interactions occurring in these solutions.

Ultrasonic Speed and Related Acoustical Parameters of 1,1ʼ-Binaphthalene-2,2ʼ-diyl Diacetate Solutions at 308.15 K

The density (ρ), viscosity (η) and ultrasonic speed (U) (2 MHz) of chloroform, THF, ethyl alcohol, ethyl acetate, 1,4-dioxane and 1,1ʼ-binaphthalene-2,2ʼ-diyl diacetate (DBNA) solutions have been determined at 308.15 K. Various acoustical parameters namely specific acoustical impedance (Z), adiabatic compressibility (κa), Van der Waals constant (b), intermolecular path length (Lf), internal pressure (π), Raoʼs molar sound function (R), relaxation time (τ), classical absorption coefficient (α/f2)cland solvation number (Sn) have been derived from ρ, η and U data and correlated with concentration (C). A fairly good to excellent correlation has been observed between a particular parameter and C. Linear increase of Z, R, b, (α/f2)cland τ (except EA) (R2= 0.90 – 0.999) and linear decrease of κs, π and Lf(R2= 0.947 – 0.995) with C supported existence of powerful molecular interactions in the solutions and further supported by nonlinear increase of Snwith C. A fairly constant Gibbs free energy of activation has been observed in all the solvent systems studied.