Exploring Pyrimidine-Based azo Dyes: Vibrational spectroscopic Assignments, TD-DFT Investigation, chemical Reactivity, HOMO-LUMO, ELF, LOL and NCI-RDG analysis

Ahlam Roufieda Guerroudj; Ehsan Ullah Mughal; Nafeesa Naeem; Amina Sadiq; Jabir H Al-Fahemi; Basim H Asghar; Nourdine Boukabcha; Abdelkader Chouaih; Saleh A Ahmed

doi:10.1016/j.saa.2024.124093

Exploring Pyrimidine-Based azo Dyes: Vibrational spectroscopic Assignments, TD-DFT Investigation, chemical Reactivity, HOMO-LUMO, ELF, LOL and NCI-RDG analysis

Spectrochim Acta A Mol Biomol Spectrosc. 2024 May 15:313:124093. doi: 10.1016/j.saa.2024.124093. Epub 2024 Feb 28.

Authors

Ahlam Roufieda Guerroudj¹, Ehsan Ullah Mughal², Nafeesa Naeem³, Amina Sadiq⁴, Jabir H Al-Fahemi⁵, Basim H Asghar⁵, Nourdine Boukabcha⁶, Abdelkader Chouaih⁷, Saleh A Ahmed⁸

Affiliations

¹ Laboratory of Technology and Solid Properties (LTPS), Abdelhamid Ibn Badis University of Mostaganem, 27000 Mostaganem, Algeria; Process Engineering Department, Faculty of Technology, Dr. Moulay Tahar University of Saïda, 20000 Saida, Algeria.
² Department of Chemistry, University of Gujrat, Gujrat-50700, Pakistan. Electronic address: ehsan.ullah@uog.edu.pk.
³ Department of Chemistry, University of Gujrat, Gujrat-50700, Pakistan.
⁴ Department of Chemistry, Govt. College Women University, Sialkot-51300, Pakistan.
⁵ Department of Chemistry, Faculty of Science, Umm Al-Qura University, Makkah 21955, Saudi Arabia.
⁶ Laboratory of Technology and Solid Properties (LTPS), Abdelhamid Ibn Badis University of Mostaganem, 27000 Mostaganem, Algeria; Chemistry Department, Faculty of Exact Sciences and Informatic, Hassiba Benbouali University, Chlef, 02000, Algeria.
⁷ Laboratory of Technology and Solid Properties (LTPS), Abdelhamid Ibn Badis University of Mostaganem, 27000 Mostaganem, Algeria.
⁸ Department of Chemistry, Faculty of Science, Umm Al-Qura University, Makkah 21955, Saudi Arabia; Chemistry Department, Faculty of Science, Assiut University, 71516 Assiut, Egypt. Electronic address: saahmed@uqu.edu.sa.

PMID: 38428162
DOI: 10.1016/j.saa.2024.124093

Abstract

Theoretical computations of pyrimidine-based azo dyes were performed by the DFT approach using the B3LYP/6 - 31G(d,p) basis set. The molecules were optimized based on the same basis set by calculating the minimum energy. FMOs, DOS and GCRD were computed for kinetic stability and chemical reactivity of the selected compounds. The MEP surface was studied to locate nucleophilic and electrophilic attack zones. The energy gap was carefully studied for pyrimidine-based azo dyes. Vibrational spectroscopy was studied in the most prominent regions with respect to PED assignments. Similarly, the UV-Vis absorption technique was calculated using the TD-DFT approach in different solvent media. The electronic structure of each atom in a molecule was examined via the electron localization function (ELF) and localized orbital locator (LOL). Non-covalent interactions were explored using reduced density gradient analysis. The combination of experimental and theoretical data allowed us to correlate the structural modifications with the observed photophysical properties, facilitating the design of azo dyes with tailored characteristics. This work contributes to the fundamental understanding of azo dyes and offers a foundation for the development of new materials with enhanced photophysical and electronic properties.

Keywords: DFT; ELF; LOL; NCI-RDG; PED; Pyrimidine-based azo dyes.