Time Domain Reflectometric Studies on Methylcellosolve – Acetylacetone Binary Solutions

Time Domain Reflectometric studies has been applied on the binary solutions of methylcellosolve (MCS) with acetylacetone (ACACT) in the entire concentration range at 298 K in the frequency range of 10 MHz – 32 GHz. The values of relaxation time (τ), effective Kirkwood correlation factor (geff ), corrective Kirkwood correlation factor (gf ) and excess permittivity (εE ) have been calculated. The relaxation time of MCS slowly decreases with increase in ACACT concentration suggesting that the size of the heteroassociated rotating unit decreases. The rate at which τ value decreases is more in MCS rich solutions which means that the formation of heteromolecular H – bonds dominantly occur in MCS rich solutions. Parallel orientation among the dipoles occur as suggested by the g^eff values which are greater than unity in all the solutions. The excess permittivity ε^E values calculated using mole and volume fractions qualitatively exhibit the same deviation from ideal behaviour.

Dielectric studies of binary mixtures of ethylene glycol mono phenyl ether with 1-butanol at different temperatures

Static permittivity ([Formula: see text]), refractive index ([Formula: see text]) and density ([Formula: see text]) of binary mixtures of ethylene glycol mono phenyl ether (EGMPE) with 1-butanol (1-BuOH) over the entire range of mole fraction and at temperatures ([Formula: see text], 313.15 and 323.15[Formula: see text]K) have been measured. From the experimental data, parameters such as excess static permittivity ([Formula: see text]), excess permittivity at optical frequency ([Formula: see text]), effective Kirkwood correlation factor ([Formula: see text]), corrective Kirkwood correlation factor ([Formula: see text]) and Bruggeman factor ([Formula: see text]) have been calculated to obtain qualitative and quantitative information about the complex formation through H-bond in binary system. In order to predict the static permittivity of polar–polar binary mixtures six mixing rules were applied and for refractive index five mixing rule were applied. Experimental results of permittivity ([Formula: see text]) and refractive index (n) are compared with those obtained from theoretical calculations. Excess parameters were fitted to the Redlich–Kister type polynomial equation.

Dielectric properties of benzylamine in 1,2,6-hexanetriol mixture using time domain reflectometry technique

The dielectric properties of binary mixtures of benzylamine-1,2,6-hexantriol mixtures at different volume fractions of 1,2,6-hexanetriol have been measured using Time Domain Reflectometry (TDR) technique in the frequency range of 10 MHz to 30 GHz. Complex permittivity spectra were fitted using Havriliak–Negami equation. By using least square fit method the dielectric parameters such as static dielectric constant ([Formula: see text]), dielectric constant at high frequency ([Formula: see text]), relaxation time [Formula: see text] (ps) and relaxation distribution parameter ([Formula: see text]) were extracted from complex permittivity spectra at 25[Formula: see text]C. The intramolecular interaction of different molecules has been discussed using the Kirkwood correlation factor, Bruggeman factor. The Kirkwood correlation factor ([Formula: see text]) and effective Kirkwood correlation factor ([Formula: see text]) indicate the dipole ordering of the binary mixtures.

DIELECTRIC RELAXATION STUDY OF BINARY MIXTURES AT DIFFERENT TEMPERATURES

<div class="Section1"><p><strong>Objective: </strong>The objective of this work is to study the intermolecular interaction and hydrogen bonding of the two binary mixtures at different temperatures which are determined from <strong>s</strong>tatic dielectric constants and their excess properties.</p><p><strong>Methods: </strong>Dielectric measurements have been carry out using a sensor which is based on frequency domain reflectometry technique. The excess dielectric properties, Kirkwood correlation factor and Bruggeman factor of the binary mixtures have also been calculated and reported in this paper.</p><p><strong>Results: </strong>The positive and negative behavior of excess dielectric permittivity and variation in linear relation in Bruggeman factor suggests the presence of intermolecular interaction in the binary mixtures. The angular Kirkwood correlation factor confirms the parallel and antiparallel orientation of the dipoles in the mixtures.</p><p>Conclusion: The static dielectric constant of binary systems increases with the addition of the volume fraction of water and decreases with increase in temperature. From excess properties, it is confirmed that there is an intermolecular interaction between the studied binary systems. Such study is useful in drug-receptor interaction.</p></div>

Dielectric Relaxation Studies of 2-Butoxyethanol with Aniline and Substituted Anilines Using Time Domain Reflectometry

The complex dielectric spectra of 2-butoxyethanol with aniline and substituted anilines like aniline, o-chloroaniline, m-chloroaniline, o-anisidine and m-anisidine binary mixtures in the composition of different volumes of percent (0%, 25%, 50%, 75%, and 100%) have been measured as a function of frequency between 10 MHz and 30 GHz at 298.15 K. The dielectric parameters like static dielectric constant ε0 and relaxation time τ have been obtained by using least square fit method. By using these parameters ε0,τ, effective Kirkwood correlation factor geff, corrective Kirkwood correlation factor gf, Bruggeman factor fB, excess dielectric constant εE, and excess inverse relaxation time 1/τE values are calculated and discussed to yield information on the dipolar alignment and molecular rotation of the binary liquid mixtures. From all the derived dielectric parameters, molecular interactions are interpreted through hydrogen bonding.