Optoelectronic Potential of Benzofuran–Oxime Compounds: Insights from UV–Vis, Optical Dispersion, and Band Gap Analysis

Year 2025, Volume: 14 Issue: 3, 293 - 304, 31.12.2025

Adnan Kurt , Murat Koca

https://doi.org/10.54187/jnrs.1744828

https://izlik.org/JA64GC88JY

Abstract

This study presents a comprehensive investigation of the electro-optical properties of two benzofuran-oxime molecules: 1-(benzofuran-2-yl)-2,2-dimethylpropan-1-one oxime (BFO) and 1-(5-bromobenzofuran-2-yl)-2,2-dimethylpropan-1-one oxime (Br-BFO). Motivated by the known optical activity of both benzofuran and oxime moieties, these compounds were synthesized to evaluate their potential for optoelectronic applications. UV–Vis spectral analysis revealed characteristic π→π* and n→π* transitions, with a notable increase in transmittance at longer wavelengths. At 325 nm, BFO exhibited a transmittance of 96.34%, while Br-BFO reached 99.49%. The optical band gaps, determined through Tauc analysis, were found to be 3.764 eV (indirect allowed) and 3.901 eV (direct allowed) for BFO, and 3.890 eV (indirect) and 3.973 eV (direct) for Br-BFO. Wavelengths corresponding to oscillator strength were measured as 273.6 nm (BFO) and 297.4 nm (Br-BFO), accompanied by calculations of refractive indices, single-oscillator energies (E0), dispersion energies (Ed), optical moments (M-1, M-3), and oscillator strengths. Notably, the Urbach energy values were 0.916 eV for BFO and 0.114 eV for Br-BFO, suggesting a higher degree of structural or electronic disorder in the former. Overall, the results suggest that both molecules may exhibit properties characteristic of organic semiconductors, indicating their potential applicability in optoelectronic materials and possible relevance in medicinal chemistry.

Keywords

Benzofuran , oxime , optical properties , dispersion parameters , electronic transitions

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