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Updated: Oct 3, 2025
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Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
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Theory of Electron Correlation in Disordered Crystals.
Stanislav P Repetsky1,2, Iryna G Vyshyvana3, Sergei P Kruchinin4
1G. V. Kurdyumov Institute for Metal Physics of the NAS of Ukraine, 03142 Kyiv, Ukraine.
Materials (Basel, Switzerland)
|February 15, 2022
Summary
This study introduces a novel method for analyzing disordered crystals, improving predictions of electronic properties. It offers a more accurate way to model electron correlations in materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Computational Physics
Background:
- Disordered crystals present challenges in accurately modeling electronic properties.
- Existing methods for electron correlation often rely on limiting cases of electron density.
- Predicting electrical conductivity and electronic spectra requires robust theoretical frameworks.
Purpose of the Study:
- To develop a new theoretical method for describing the electronic spectrum and electrical conductivity of disordered crystals.
- To incorporate electron correlations in a general case of arbitrary electron density.
- To enable accurate numerical calculations and property predictions for disordered systems.
Main Methods:
- Utilizing the tight-binding model for electronic states.
- Deriving Green's functions and electrical conductivity via the diagram method.
- Obtaining exact equations for elementary excitation spectra and vertex parts.
Main Results:
- Developed a method to describe electron correlations for arbitrary electron densities.
- Derived a cluster expansion for the density of states and electrical conductivity.
- Demonstrated that electron scattering contributions decrease with increasing cluster size.
Conclusions:
- The new method provides a more comprehensive approach to understanding disordered crystalline systems.
- Accurate numerical predictions of energy spectra and material properties are achievable.
- The findings advance the theoretical understanding of electron behavior in disordered materials.
Keywords:
Green’s functionsdensity of statesdiagram technicsdisordered crystalselectrical conductivityelectronic spectrumfree energythe Hamiltonian of electrons and phononsthe mass operator of the Green’s functionthe temperature Green’s functionsMore Related Videos
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