DIELECTRIC RELAXATION IN BROMOBENZENE-BENZENE AND BROMOBENZENE-HEXANE BINARY SYSTEMS: THERMODYNAMIC ANALYSIS AND SOLVENT INFLUENCE
S.T. Azizov1, S.A. Nabieva1, V.M. Hajiyeva1, S.I. Qulieva2
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ABSTRACT

This paper presents the results of an experimental study of the complex dielectric permittivity (ε' and ε") of bromobenzene-benzene and bromobenzene-hexane binary systems in the microwave range (λ = 12.8 mm) at temperatures from 293 K to 193 K. The aim of the study is to establish the relationship between molecular dynamics, thermodynamic parameters, and the nature of the solvent in the process of dielectric relaxation. The temperature dependence of the dielectric relaxation time (τ) for each system was determined. It was found that an increase in the size of the halogen substituent leads to an increase in τ. Based on the theory of absolute reaction rates, the thermodynamic parameters of relaxation process activation were calculated: free energy (ΔF), enthalpy (ΔH), and entropy (ΔS). The influence of intermolecular interactions and solvent structure on energy barriers and system order in the process of dipole reorientation is shown.

Keywords: dielectric relaxation, bromobenzene, benzene, hexane, thermodynamics, microwave range, relaxation time, intermolecular interactions.
DOI:10.70784/azip.1.2026116

Received: 08.01.2026
Internet publishing: 22.01.2026    AJP Fizika E 2026 1 en p.15-20

AUTHORS & AFFILIATIONS

1. Ministry of Science and Education Republic of Azerbaijan, Institute of Physics,
2. Baku Business University, Baku, Azerbaijan
E-mail: 1. Corresponding Author: samirazizov2012@gmail.com
2. ibrahimqizisvetlana@gmail.com
1. ORCID: https://orcid.org/0000-0001-6252-1512

Graphics and Images

         

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