Core-expanded pi-systems: models for graphene nanoribbons

Graphene nanoribbons (GNRs), for which the width of the sheet is confined to be a finite size while the length is considered infinitely long, have attracted considerable interest due to their high potential for technological applications in nanoelectronics.

Structural and electronic properties of Functionalized GNRs (synthesized in the group of Zhaohui Wang (Beijing) by repeating the PBI unit in one dimension, that is, designing poly-PBIs) are determined by quantum-chemical investigations at DFT and TDDFT level supplemented with modeling of vibronic structures in the framework of the Franck-Condon  approximation. Structural isomers of core-expanded pi-systems are identified by comparing computed and observed absorption spectra, circular dichroism spectra, NMR spectra, etc...


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