Shedding Light on Structure–Property Relationships for Conjugated Microporous Polymers: The Importance of Rings and Strain

Abstract

The photophysical properties of insoluble porous pyrene networks, which are central to their function, differ strongly from those of analogous soluble linear and branched polymers and dendrimers. This can be rationalized by the presence of strained closed rings in the networks. A combined experimental and computational approach was used to obtain atomic scale insight into the structure of amorphous conjugated microporous polymers. The optical absorption and fluorescence spectra of a series of pyrene-based materials were compared with theoretical time-dependent density functional theory predictions for model clusters. Comparison of computation and experiment sheds light on the probable structural chromophores in the various materials.

Molecular Porous Photosystems Tailored for Long‐Term Photocatalytic CO2 Reduction

“…To gain insight into the influence of the nature of the chromophores on their electronic structure and the corresponding molecular frontier orbitals, DFT calculations were performed on molecular cluster models . Here we anticipated that the molecular frontier orbitals of the constitutive molecular unit are representative of those of the solids.…”

Function-led design of new porous materials

“…This modular philosophy, where the molecular building blocks encode the target function, also applies to electronic properties. For instance, electronic structure calculations for photocatalytic CMPs (24,25) showed that the electronic properties of the polymer can be represented by small clusters of just a few monomer units (26).…”

Insight into the self-assembly of water-soluble perylene bisimide derivatives through a combined computational and experimental approach

“…Such a blue shift is a well-known artefact 65 of the use of range-separated functionals such as ωB97X, which avoid issues with the description of charge-transfer states, but at the expense of slightly blue shifting the overall spectrum. Indeed, in previous work 5,66 we have often applied a rigid ad hoc shift to correct for this, though we do not do that here. The second and more interesting observation is that, if we assume that the evolution of the experimental UV-Vis spectrum after addition of GdL is due to aggregation, experiment and our calculations agree on both the absence of large shifts in the spectrum upon aggregation and the decrease in absorption intensity.…”