Energy Structure of the Long-Wavelength Absorption Spectra Edge and Its Relationship to the Urbach Energy Eu and the Optical Band Gap Eg of C60 Films with Thicknesses of 5000 and ~1000 nm

Authors

  • M.P. Gorishnyi Institute of Physics, Nat. Acad. of Sci. of Ukraine, Department of Molecular Photoelectronics

DOI:

https://doi.org/10.15407/ujpe71.9.705

Keywords:

film, absorption spectrum, C60 and C70 fullerenes, approximation, Gaussian function, Gaussian

Abstract

The long-wavelength edge of the absorption spectra of C60 films with a thickness of 5000 and ∼1000 nm in the regions of 1.414–1.998 eV and 1.448–2.371 eV, respectively, was approximated by the sum of Gaussian functions (Gaussians). In C60 films with a thickness of 5000 nm, this edge is formed by the sum of Gaussians centered at 1.829 and 2.026 eV, whereas in C60 films with a thickness of ∼1000 nm, it is formed by the sum of Gaussians centered at 1.800, 1.894, 2.025 and 2.382 eV. The main contribution to the absorption of C60 films with thickness of 5000 nm is provided by the Gaussian centered at 2.026 eV, whereas in in C60 films with thickness of ∼1000 nm – by Gaussians centered at 1.894, 2.025, and 2.382 eV. The Eu values vary within the ranges of 12.15–47.69 meV and 28.04–108.44 meV, and Eg – within the ranges of 1.653–1.718 eV and 1.524–1.769 eV in C60 films with a thickness of 5000 and ∼1000 nm, respectively.

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Published

2026-09-07

Issue

Vol. 71 No. 9 (2026)

Section

Optics, atoms and molecules

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How to Cite

Energy Structure of the Long-Wavelength Absorption Spectra Edge and Its Relationship to the Urbach Energy Eu and the Optical Band Gap Eg of C60 Films with Thicknesses of 5000 and ~1000 nm. (2026). Ukrainian Journal of Physics, 71(9), 705. https://doi.org/10.15407/ujpe71.9.705

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