Rebaz Kareem - Physics Department, College of Science, University of Halabja, ۴۶۰۱۸, Halabja, Iraq
Mehmet Hanifi Kebiroğlu - Department of Opticianry, Darende Bekir Ilicak Vocational School, Malatya Turgut Ozal University, Malatya, Türkiye
Othman Abdulrahman Hamad Hamad - University of Raparin, College of Science, Department of Chemistry۴۶۰۱۲, Sulamani, Iraq
Omer Kaygili - Department of Physics, Faculty of Science, Firat University, ۲۳۱۱۹, Elazig, Türkiye
Niyazi Bulut - Department of Physics, Faculty of Science, Firat University, ۲۳۱۱۹, Elazig, Türkiye

This study employs Density Functional Theory (DFT) methodology to comprehensively investigate the structural and physicochemical characteristics of epinephrine, a molecule of physiological relevance. By employing DFT approaches, a more precise description of epinephrine's structure and properties is achieved compared to prior studies. A detailed examination of epinephrine's structure and various properties, such as the Highest Occupied Molecular Orbital (HOMO), Lowest Unoccupied Molecular Orbital (LUMO), Band Gap (BG), Density of States (DOS), Fourier-Transform Infrared Spectroscopy (FT-IR), Ultraviolet (UV) absorption, and Natural Bond Orbital (NBO) analysis. Furthermore, we explore non-covalent interactions (NCI) through the examination of Reduced Density Gradient (RDG) and Molecular Electrostatic Potential (MEP) maps. Incorporating FT-IR results, we delve into the vibrational properties of epinephrine, highlighting C-H vibrations at ۳۷۰۰, ۳۱۷۶.۲۰, and ۲۹۸۶.۱۴ cm-۱, along with specific vibrational modes of the benzene ring at ۱۵۵۸.۴۳ and ۱۴۶۱.۱۴ cm-۱. Additionally, we provide a comprehensive analysis of epinephrine's thermochemical properties at temperatures ranging from ۱۰۰ to ۲۰۰ K under constant pressure conditions (۱ atm), including optical transitions. This comprehensive investigation enhances our understanding of epinephrine's structure and properties, paving the way for a more profound comprehension of its biological and pharmacological significance.

Epinephrine, Physicochemical, Thermochemistry, Optical properties, NCI, RDG