Dielectric relaxation of benzonitrile and tetramethyl urea with N, methylformamide in C6H6 under 9.885 GHz electric field

Abstract

Dielectric relaxation of binary (jk) polar mixtures of benzonitrile and tetramethyl urea (TMU) with N,methylformamide (NMF) dissolved in benzene (i) for different weight fractions w_jk’s of polar solutes and mole function x_j’s of NMF at 25, 30, 35 and 40 °C have been studied in terms of relaxation time τ_jk and dipole moment µ_jk from conductivity measurement of solution under 9.885 GHz electric field using Debye Model. Solute-solvent and solute-solute association have been predicted from plot of τ_jk and µ_jk against x_j’s of NMF up to x_j=0.5 and beyond x_j=0.5 to x_j= 1.0, respectively. Estimated τ and µ from both the proposed methods agree with the reported values. Theoretically µ’s have been calculated from bond angles and bond moments of polar groups due to existence of inductive, mesmeric and electromeric effect arising out of microscopic inhomogeneity in them. Molecular dynamics of polar mixtures have been ascertained from Eyring rate equation to establish Debye relaxation mechanism for all systems.