The electronic structure of free radical 9-fluorenyl within the framework of QTAIM
E.M. Chernova1, Yu..D. Orlov1, E.A. Miroshnichenko2
1 Tver State University
2 N.N. Semenov Federal Research Center for Chemical Physics of the RAS
DOI: 10.26456/pcascnn/2025.17.514
Original article
Abstract: The paper presents the results of studying the influence of free valence on the electronic structure of 9-fuorenyl radical in comparison with the fluorene molecule. The geometric structure and electron density distributions in the above compounds were calculated using the density functional method B3LYP/6-311++G(3df,3pd) 6d 10f. The electronic structure of the studied compounds was investigated within the framework of the «quantum theory of atoms in a molecule». The total electron density of the compounds under consideration was divided into spatial areas («topological» atoms) combined for analysis into atomic groups. Their electronic parameters were calculated: charge, volume, and spin density (for radicals). A comparative analysis of the parameters of atomic groups in the molecule and radical was performed. The characteristics of bond critical points and cycle critical points were obtained and analyzed. The concepts of «radical center» and «free valence» are quantitatively characterized, and the conjugation of free valence in 9-fluorenyl is shown through the distribution of spin density.
Keywords: fluorene, 9-fluorenyl, quantum theory of atoms in a molecule, electron density, spin density, free valence, radical center
- Elena M. Chernova – Head of the Basic Educational Laboratory, General Physics Department, Tver State University
- Yuri D. Orlov – Head of the General Physics Department, Tver State University
- Evgeny A. Miroshnichenko – Chief Researcher, Burning and Explosion Department, N.N. Semenov Federal Research Center for Chemical Physics of the RAS
For citation:
Chernova E.M., Orlov Yu..D., Miroshnichenko E.A. Elektronnoe stroenie svobodnogo radikala 9-fluorenil v ramkakh QTAIM [The electronic structure of free radical 9-fluorenyl within the framework of QTAIM], Fiziko-khimicheskie aspekty izucheniya klasterov, nanostruktur i nanomaterialov [Physical and chemical aspects of the study of clusters, nanostructures and nanomaterials], 2025, issue 17, pp. 514-521. DOI: 10.26456/pcascnn/2025.17.514. ⎘
Full article (in Russian): download PDF file
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