<p>Singlet Fission (SF) has demonstrated significant
promise for boosting the power conversion efficiency (PCE) of solar cells.
Traditionally, SF is targeted as an intermolecular process, however its
dependence on crystal packing makes molecular design difficult. In contrast,
intramolecular SF (iSF) enables the exploration of tunable bi-chromophoric
systems following well-defined structure-property relationships. In this work,
we propose a set of parameters to screen conjugated donor-acceptor copolymer
candidates with potential iSF behaviour. We focus our analysis on the E(S<sub>1</sub>)>2E(T<sub>1</sub>)
thermodynamic condition and on the appropriate charge transfer (CT) character
of S<sub>1</sub>. We map the CT character with respect to the frontier
molecular orbital (FMO) energies of the constituent monomers, providing a
cost-effective protocol for an accelerated screening of promising iSF
donor-acceptor pairs, while minimizing the number of computations. These
parameters are applied to a chemically diverse, curated library of 81 truncated
dimers of synthetically feasible donor-acceptor copolymers. From our dataset,
four candidates are flagged for iSF, two of which were previously
experimentally reported. This protocol is envisioned to be scaled up for the high-throughput
screening of large databases of donor-acceptor dimers for the design and
identification of conjugated polymers capable of iSF. </p>
Molecular design strategy for practical singlet fission materials: The charm of donor/acceptor decorated quinoidal structure
