Torsion Angles between Donor and Acceptor Moieties as a Descriptor for Designing Nonlinear Optics and Thermally Activated Delayed Fluorescence Materials

Intramolecular boron-locking strategy induced remarkable first hyperpolarizability: role of torsion angles between donor and acceptor units

“…What's more, it has been confirmed that the inherent properties are closely related to torsion angles between the donor and acceptor units. 9 As a consequence, the changes of θ 1 and θ 2 will cause the inherent property of β to vary remarkably.…”

“…2,10,11 In terms of those effective approaches to enhance hyperpolarizabilities, constructing organic molecules with donor–acceptor (D–A) architecture has emerged as a hot topic. 6–9,12–14 Moreover, it has been confirmed that inherent NLO properties, such as the first hyperpolarizability, are closely related to the torsion angle between donor and acceptor moieties, which demonstrates that controlling torsion angles between donor and acceptor units has become a key factor for obtaining high performance NLO materials. 8,9,15–17 To data, it is still an open issue to find a robust approach to control torsion angles to achieve high performance NLO materials.…”

“…In recent years, the field of nonlinear optics (NLO) has received much attention as researchers aim to design high performance NLO materials to meet the growing requirements of practical applications in dynamic image processing, optical frequency conversion and data storage. 1–9 Great effort has been put into designing NLO materials with large hyperpolarizabilities, consequently, some effective approaches to enhance hyperpolarizabilities have been proposed. 2,10,11 In terms of those effective approaches to enhance hyperpolarizabilities, constructing organic molecules with donor–acceptor (D–A) architecture has emerged as a hot topic.…”

“…Recently, strategies to design high performance NLO materials by controlling the torsion angles between donor and acceptor fragments have been proposed. 8,9,15–17 For instance, installing large groups into the donor and acceptor units has been proposed by Lou and co-workers, 15–17 which uses the steric hindrance of large groups to regulate torsion between the donor and acceptor moieties. However, large groups are difficult to insert into donor and acceptor fragments to create the small torsion angles between the donor and acceptor units; importantly, large hyperpolarizabilities of D–A organic molecules commonly correspond to small torsion angles.…”

“…However, large groups are difficult to insert into donor and acceptor fragments to create the small torsion angles between the donor and acceptor units; importantly, large hyperpolarizabilities of D–A organic molecules commonly correspond to small torsion angles. 9 In our previous work 8,9 we reported that the intramolecular carbon-locking strategy can serve as an effective strategy to obtain small torsion angles between donor and acceptor moieties, thereby predicting a series of candidate NLO materials with large hyperpolarizabilities. But, those NLO materials lacked strong intramolecular/intermolecular noncovalent interactions (INCIs), which is key for stability.…”