Clar Rules the Electronic Properties of 2D π-Conjugated Frameworks: Mind the Gap

Chemistry. 2020 May 20;26(29):6569-6575. doi: 10.1002/chem.201905087. Epub 2020 Feb 25.

Abstract

The key electronic properties of a family of 2D frameworks structurally convergent with holey graphenes were studied. The bandgap of these materials decreases monotonically with size, showing a common trend with anthracenes and kekulenes. This was rationalized by Clar's sextet rule, which reveals a direct relationship between the molecular systems and the 2D frameworks. In addition, a detailed benchmark against experimental data showcased the high quality of the models, which reproduce accurately available electronic properties. Overall, it was shown that DFT can be used to screen and understand the intrinsic bandgaps and electrochemistry potentials for technological applications prior to the synthesis of π-conjugated porous materials.

Keywords: Clar's rule; acenes; covalent organic frameworks; holey graphene; kekulene.