Electron-lattice dynamics in π-conjugated systems

The work presented in this thesis concerns the dynamics in π-conjugated hydrocarbon systems. Due to the molecular bonding structure of these systems there exists a coupling between the electronic system and the phonons of the lattice. If this interaction, which is referred to as the electron-phonon (e-ph) coupling, is sufficiently strong it may cause externally introduced charge carriers to self-localize in a polarization cloud of lattice distortions. These quasi-particles are, if singly charged, termed polarons, the localization length of which, aside from the e-ph coupling strength, also depend upon the structural and energetic disorder of the system. In disordered systems localization is strong and transport is facilitated by nonadiabatic hopping of charge carriers from one localized state to the next, whereas in well-ordered systems, where extended states are formed, adiabatic transport models apply…

Contents

1 Introduction and outline of thesis
1.1 A brief introduction to organic electronics
1.2 Outline of thesis
2 Properties of π-conjugated systems
2.1 Fundamental aspects
2.2 Molecules and π-conjugated systems
2.3 Semiconducting organic solids
2.4 Charge transport in organic semiconductors
2.5 Characterization of charge transport
2.6 Excitation and relaxation dynamics
3 Electron transfer
3.1 The electron transfer Hamiltonian
3.2 The electronic-nuclei Hamiltonian
3.3 Regimes of electron transfer
3.4 The impact of disorder
3.5 Charge transport in disordered systems
3.6 Charge transport in well-ordered systems
4 Methodological approach
4.1 General considerations
4.2 Model approximations
4.3 Statics
4.4 Dynamics
5 Comments on papers
5.1 Electron-lattice dynamics in CPs
5.1.1 Paper I:Transport along chains with static ring torsion
5.1.2 Paper II:Transport along chains with dynamic ring torsion
5.1.3 Paper III:Localization due to ring torsion dynamics
5.2 Electron-lattice dynamics in MCs
5.2.1 Paper IV:Transport dynamics in MCs with local e-ph coupling
5.2.2 Paper V:Internal conversion dynamics in MCs
6 Outlook
Bibliography

Author: Hultell (Andersson), Magnus

Source: Linköping University

Download URL 2: Visit Now

Leave a Comment