Charge delocalization characteristics of regioregular high mobility polymers

Area of Science:

• Materials Science
• Organic Electronics
• Computational Chemistry

Background:

• Regioregularity in conjugated polymers significantly impacts optoelectronic properties.
• Improved charge carrier mobility in field-effect transistors is linked to structural control.
• Understanding atomistic factors is crucial for designing efficient organic electronic materials.

Purpose of the Study:

• To investigate the effect of regioregularity on hole transport properties in conjugated polymers.
• To compare structural and electronic characteristics of regioregular and regiorandom oligomers.
• To provide foundational insights for modeling charge transport in organic semiconductors.

Main Methods:

• Density functional theory (DFT) calculations were employed.
• Regioregular and regiorandom oligomers, modeling polymer structures, were studied.
• Key parameters including chain planarity, cation spin density, excess charges, and reorganization energy were analyzed.

Main Results:

• The primary difference identified between regioregular and regiorandom oligomers is backbone planarity.
• Reorganizational energies were found to be similar across both types of oligomers.
• DFT analysis provided detailed electronic and structural comparisons.

Conclusions:

• Backbone planarity is a critical factor influenced by regioregularity, affecting hole transport.
• Reorganizational energy differences do not significantly distinguish between regioregular and regiorandom structures.
• This research is a foundational step towards modeling charge transport by linking atomistic details to polymer backbone structure.