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Halogen Doping to Control the Band Gap of Ascorbic Acid: A Theoretical Study
Ibrahim Isah Nasidi1, Omer Kaygili1, Abdul Majid2
1Department of Physics, Faculty of Science, Firat University, 23119 Elazig, Turkey.
ACS Omega
|December 12, 2022
Summary
Structural modification of ascorbic acid using halogen doping (fluorine, chlorine, bromine) alters its electronic and spectroscopic properties. The study found that the band gap is sensitive to the type of halogen used for doping.
Area of Science:
- Biochemistry
- Computational Chemistry
- Materials Science
Background:
- Ascorbic acid, a vital antioxidant, plays a role in numerous physiological processes.
- Structural modifications of ascorbic acid are crucial for understanding its electron transport, redox reactions, and chemotherapeutic potential.
Purpose of the Study:
- To investigate the impact of halogen doping (F, Cl, Br) on the electronic structure and spectroscopic properties of ascorbic acid.
- To explore changes in optical and electrical properties through first-principles calculations.
Main Methods:
- Geometry optimization using Density Functional Theory (DFT) and Hartree-Fock methods with various basis sets.
- Computation of potential energy maps, UV-vis, NMR, and FT-IR spectra.
- First-principles calculations to analyze electronic structure and spectroscopic parameters.
Main Results:
- Lowest-energy structures were determined for halogen-doped ascorbic acid.
- Doping significantly affects the electronic structure, optical, and electrical properties.
- The band gap was found to be sensitive to the specific halogen dopant, decreasing from F to Cl to Br.
Conclusions:
- Halogen doping is an effective strategy to tune the properties of ascorbic acid.
- The observed sensitivity of the band gap to halogen type provides insights for designing novel functional materials.
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