Theoretical analysis of a pyrrole-based compound: Insights into electronic properties and spectroscopic behavior via DFT and TD-DFT

نویسندگان

1 Laboratory of Engineering in Chemistry and Physics of Matter, Faculty of Sciences and Technics, Sultan Moulay Slimane University, Beni Mellal, Morocco.

2 Laboratory of Engineering in Chemistry and Physics of Matter, Faculty of Sciences and Technics, Sultan Moulay Slimane University, Beni Mellal, Morocco.

3 Laboratory of Engineering in Chemistry and Physics of Matter, Faculty of Sciences and Technics, Sultan Moulay Slimane University, Beni Mellal, Morocco.

4 Laboratory of Engineering in Chemistry and Physics of Matter, Polydisciplinary Faculty of Khouribga, Sultan Moulay Slimane University, Beni Mellal, Morocco.

5 Laboratory of Engineering in Chemistry and physics of Matter, Faculty of Medicine and Pharmacy, Sultan Moulay Slimane University, Beni Mellal, Morocco.

6 Laboratory of Engineering in Chemistry and Physics of Matter, Faculty of Sciences and Technics, Sultan Moulay Slimane University, Beni Mellal, Morocco.

7 Laboratory of Engineering in Chemistry and Physics of Matter, Faculty of Sciences and Technics, Sultan Moulay Slimane University, Beni Mellal, Morocco.

8 Laboratory of Engineering in Chemistry and Physics of Matter, Faculty of Sciences and Technics, Sultan Moulay Slimane University, Beni Mellal, Morocco.

9 Laboratory of Engineering in Chemistry and Physics of Matter, Faculty of Sciences and Technics, Sultan Moulay Slimane University, Beni Mellal, Morocco.

10 Laboratory of Engineering in Chemistry and Physics of Matter, Faculty of Sciences and Technics, Sultan Moulay Slimane University, Beni Mellal, Morocco.

doi
10.22034/crl.2026.580037.1828
چکیده

A comprehensive density functional theory (DFT) and time-dependent DFT (TD-DFT) investigation was conducted to elucidate the structural, electronic, and spectroscopic properties of a pyrrole-based heterocyclic compound, namely 3-(5-phenyl-1-(pyridin-3-yl)-1H-pyrrol-2-yl)propanoic acid. The optimized geometry at the B3LYP/6-311G(d.p) level confirmed the stability of the molecular structure, supported by the absence of imaginary frequencies. The calculated HOMO–LUMO energy gap (4.28 eV) indicates significant kinetic stability and low chemical reactivity. Molecular electrostatic potential (MEP) analysis revealed that oxygen and nitrogen atoms constitute the most nucleophilic regions. TD-DFT calculations, including solvent effects, predicted a dominant π→π* transition at 281 nm, characteristic of conjugated systems. Furthermore, NMR chemical shifts calculated using the GIAO method showed excellent agreement with experimental data (R² ≈ 0.99), outperforming other approaches. These findings highlight the reliability of the computational protocol and provide valuable insights into the physicochemical behavior of pyrrole-based systems.