Simulation of Charge Distribution and Microstructure in Semicrystalline Polymeric Ionic-Electronic Conductors Using
Zixuan Wei1, Hesam Makki1,2, Paola Carbone3
1Department of Chemistry, University of Liverpool, Crown Street, Liverpool L69 7ZD, UK.
Journal of Chemical Theory and Computation
|March 6, 2026
Summary
We developed a new simulation method to study how charge distribution changes in polymeric organic mixed ionic-electronic conductors (OMEICs) under constant electrochemical potential, revealing minimal structural changes and localized redox events.
Area of Science:
- Materials Science
- Computational Chemistry
- Polymer Science
Background:
- Understanding charge distribution in polymeric organic mixed ionic-electronic conductors (OMEICs) is vital for their application.
- Studying these changes under constant electrochemical potential is experimentally challenging.
Purpose of the Study:
- Introduce a novel simulation methodology for classical atomistic simulations of doped semiconductors at constant electrochemical potential.
- Enable individual polymer chain oxidation/reduction based on their redox potentials and external electrochemical potential.
Main Methods:
- Employ a grand-canonical molecular dynamics (GC-MD) scheme.
- Utilize a QM/MM Hamiltonian to describe local redox potential modulation.
- Apply the method to semicrystalline polymers with layered and lamellar structures.
Main Results:
- Reproduce experimentally observed minimal structural changes in polymers across various electrochemical potentials and charging levels.
- Identify increased fluctuations in charging levels and pronounced interlamellar angle variations near the redox potential.
- Observe no significant charge correlation between neighboring chains, except at highly negative potentials.
Conclusions:
- The developed method provides a robust framework for simulating charge distributions in dynamically doped systems.
- Offers new insights into polymer structural responses under constant electrochemical potentials.
- Highlights the link between single-chain conformation and its redox behavior.
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