Study of the H-bond interaction on binary mixtures of nitromethane with primary alcohols at different temperatures using dielectric parameters

Abstract

A dielectric spectroscopic study has been carried out on binary mixtures of polar nitromethane (NM) with primary alcohols: ethanol (ETH), 1-propanol (1-PRO) and 1-butanol (1-BUT) at different temperatures. The complex dielectric spectra of pure and binary mixtures were described by Debye model. The dielectric constant (e0), relaxation time (τ), and dielectric constant at an optical frequency (e∞) of binary mixtures were determined at various temperatures. The computed excess dielectric parameters were used to interpret the intermolecular interaction between the unlike dipoles within the binary mixture system. From the experimental analysis, it is confirmed that, the mixture molecules form H-bond complex structure and dipoles are aligned in anti-parallel direction. Among all the binary systems, strong H-bond interaction can be seen in NM + 1-PRO mixture system. Rapid decrement of relaxation time for NM + 1-BUT binary system results higher amount of structural changes symmetry breaking effect. The formation of hydrogen bonding interaction between oxygen atom of nitro groups in NM and hydrogen atom of alcohols in binary mixture systems was confirmed by FTIR analysis.