The bis (ethylenedithio) tetraselenafulvalene (BEDT-TSF) molecular system is a fundamental structural element from which low-dimensional organic conductors and superconductors are formed. In this work, a comprehensive study of the physical properties of an isolated neutral BEDT-TSF molecule in its ground state was conducted using density functional theory (DFT) methods. Within the framework of a consistent quantum-mechanical approach, the spectrum of single-electron states near the Fermi surface (frontier molecular orbitals) was initially determined, and the Kohn–Sham HOMO–LUMO orbital energy gap was calculated. Based on the electron density distribution, the spatial configuration of the nuclei was optimized, and the macroscopic thermodynamic characteristics of the system were calculated. Analysis of the matrix of second derivatives of the energy with respect to nuclear coordinates confirmed the dynamic stability of the structure (complete absence of imaginary frequencies) and allowed for a detailed description of the phonon spectrum of normal harmonic vibrations, which determines the parameters of the electron-phonon interaction in condensed phases of charge-transfer salts.
Quantum-Mechanical Modeling of The Electronic Structure, Spatial Configuration, And Vibrational Dynamics of The Bis (Ethylenedithio) Tetraselenafulvalene (BEDT-TSF) Molecule
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Abstract
References
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