Vol. 25 No. 1 (2026): Mapana Journal of Sciences
Physical Sciences

Comparative studies of photophysical properties of Indole molecules

  • Vijayalaxmi Mallayya
Vijayalaxmi Mallayya
Gulbarga University Kalaburagi

Published 2026-02-14

Keywords

  • Dipole moment,
  • Indole derivative,
  • Solvatochromatic and Gaussian 16 W

Copyright (c) 2026

Creative Commons License

This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.

Abstract

              In this study, we present a comparative investigation of 5-methyl-3-phenyl-1H-indole-2-carbohydrazide and 5-chloro-3-phenyl-1H-indole-2-carbohydrazide. The work includes molecular structure determination, UV–visible spectral analysis, and evaluation of 1H and 13C NMR chemical shift values. The influence of pure solvents on the spectral characteristics was analysed using solvatochromic theories. Ground- and excited-state dipole moments were calculated using the solvatochromic method. The higher excited-state dipole moment values and the observed redshifts in the emission spectra confirm that the singlet excited state exhibits intramolecular charge-transfer (ICT) character. Theoretical studies were performed using density functional theory (DFT) at the CAM-B3LYP/6-31+G(d,p) level with Gaussian software. The HOMO and LUMO energies, along with the global chemical reactivity descriptors (GCRD), were evaluated using the DFT/B3LYP/6-311+G(d,p) level of theory. Additionally, molecular electrostatic potential (MEP) maps were constructed to determine the region’s most susceptible to electrophilic and nucleophilic attack. The experimentally measured ground-state dipole moments (1.67 D and 13.1 D) were found to be higher than the corresponding theoretical values (1.11 D and 6.44 D).

 

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