Modeling the electronic structure of organic materials: A solid-state physicist's perspective

Abstract

Modeling the electronic and optical properties of organic semiconductors remains a challenge for theory, despite the remarkable progress achieved in the last three decades. The complexity of these systems, including structural (dis)order and the still debated doping mechanisms, has been engaging theorists with different backgrounds. Regardless of the common interest across the various communities active in this field, these efforts have not led so far to a truly interdisciplinary research area. In the attempt to move further in this direction, we present our perspective as solid-state theorists for the study of molecular materials in different states of matter. Considering exemplary systems belonging to well-known families of oligo-acenes and -thiophenes, we provide a quantitative description of electronic properties and optical excitations obtained with state-of-the-art first-principles methods such as density-functional theory and many-body perturbation theory. Simulating the systems as gas-phase molecules, clusters, and periodic lattices, we are able to identify short- and long-range effects in their electronic structure. While the latter are usually dominant in organic crystals, the former play an important role, too, especially in the case of donor/acceptor complexes. Furthermore, we demonstrate the viability of implicit schemes to evaluate band gaps of molecules embedded in isotropic and even anisotropic environments, in quantitative agreement with experiments. In the context of doped organic semiconductors, we show how the crystalline packing enhances the favorable characteristics of these systems for opto-electronic applications. The counter-intuitive behavior predicted for their electronic and optical properties is deciphered with the aid of a tight-binding model, which represents a connection to the most common approaches to evaluate transport properties in these materials.

References in corpus (50)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Advanced capabilities for materials modelling with Quantum ESPRESSO
• Optimized norm-conserving Vanderbilt pseudopotentials
• Maximally localized Wannier functions: Theory and applications
• Wannier90 as a community code: new features and applications
• The GW method
• Relativistic Solar Cells
• Optimization Algorithm for the Generation of ONCV Pseudopotentials
• Yambo: an \textit{ab initio} tool for excited state calculations
• Renormalization of Molecular Electronic Levels at Metal-Molecule Interfaces
• Relativistic quasiparticle self-consistent electronic structure of hybrid halide perovskite photovoltaic absorbers
• Revealing the role of organic cations in hybrid halide perovskites CH3NH3PbI3
• Real-space grids and the Octopus code as tools for the development of new simulation approaches for electronic systems
• Many-body perturbation theory calculations using the yambo code
• An exact Coulomb cutoff technique for supercell calculations
• Long-range/short-range separation of the electron-electron interaction in density functional theory
• First-principles GW calculations for fullerenes, porphyrins, phtalocyanine, and other molecules of interest for organic photovoltaic applications
• Octopus, a computational framework for exploring light-driven phenomena and quantum dynamics in extended and finite systems
• Hybrid, Gate-Tunable, van der Waals p-n Heterojunctions from Pentacene and MoS2
• Role of Polar Phonons in the Photo Excited State of Metal Halide Perovskites
• How dielectric screening in two-dimensional crystals affects the convergence of excited-state calculations: Monolayer MoS${}_2$
• Polarization-induced renormalization of molecular levels at metallic and semiconducting surfaces
• Quasiparticle and Optical Spectroscopy of Organic Semiconductors Pentacene and PTCDA from First Principles
• GW quasiparticle band gap of the hybrid organic-inorganic perovskite CH${}_3$NH${}_3$PbI${}_3$: Effect of spin-orbit interaction, semicore electrons, and self-consistency
• Solid state effects on exciton states and optical properties of PPV
• Simulating pump-probe photo-electron and absorption spectroscopy on the attosecond time-scale with time-dependent density-functional theory
• Structural and excited-state properties of oligoacene crystals from first principles
• Phonon Screening of Excitons in Semiconductors: Halide Perovskites and Beyond
• Origins of singlet fission in solid pentacene from an ab initio Green's-function approach
• Temperature Renormalization of Optical Spectra of Monolayer MoS2
• Exciton Dissociation Dynamics in Model Donor-Acceptor Polymer Heterojunctions: I. Energetics and Spectra
• Optical spectra from molecules to crystals: Insight from many-body perturbation theory
• Correlated electron-hole mechanism for molecular doping in organic semiconductors
• Understanding real-time time-dependent density-functional theory simulations of ultrafast laser-induced dynamics in organic molecules
• Optical properties and charge-transfer excitations in edge-functionalized all-graphene nanojunctions
• Band gap renormalization, carrier mobilities, and the electron-phonon self-energy in crystalline naphthalene
• Ab initio Simulation of Optical Limiting: The Case of Metal-Free Phthalocyanine
• SAMPLE: Surface structure search enabled by coarse graining and statistical learning
• Conditions for electronic hybridization between transition-metal dichalcogenide monolayers and physisorbed carbon-conjugated molecules
• Optical properties of azobenzene-functionalized self-assembled monolayers: Intermolecular coupling and many-body interactions
• On the Possibility of Singlet Fission in Crystalline Quaterrylene
• Quasiparticle electronic structure of phthalocyanine:TMD interfaces from first-principles $GW$
• Long-Range Order Promotes Charge-Transfer Excitations in Donor/Acceptor Co-Crystals
• Nonlinear Light Absorption in Many-Electron Systems Excited by an Instantaneous Electric Field: A Non-Perturbative Approach
• Donors, Acceptors, and a Bit of Aromatics: Electronic Interactions of Molecular Adsorbates on hBN and MoS${}_2$ Monolayers
• LayerPCM: An implicit scheme for dielectric screening from layered substrates
• Understanding effects of packing and chemical terminations on the optical excitations of azobenzene-functionalized self-assembled monolayers
• LayerOptics: Microscopic modeling of optical coefficients in layered materials
• Polymorphism in $\alpha$-sexithiophene crystals: Relative stability and transition path
• Polarization Resolved Optical Excitation of Charge-Transfer Excitons in PEN:PFP Co-Crystalline Films: Limits of Non-Periodic Modelling