Many reported TADF emitters are claimed to enjoy intramolecular H-bonding interactions, although direct evidence for such interactions is scarce. Here we investigate an exemplar series or such materials, and using computation energy surfaces find that H-bonding is most likely inactive in this series. It remains unclear whether such interactions are truly present in other reported examples, although computational energy surfaces may help distinguish this in future.
A plethora of various colour TADF emitters was reported during the recent years. However, only few deep blue emitters possessing good colour purity as well as relevant stability were introduced [1-3].
For efficient TADF to take place, the occurrence of strong charge transfer is required. In turn, charge transfer demands the presence of fairly strong donor and acceptor units, which usually have a rigid molecular skeleton. However, the involvement of strong chromophores is known to lower the values of 1CT and 3LE states, which makes it difficult to obtain deep blue emission, even though vanishing ∆EST can be reached. Therefore, in order to design a deep blue TADF emitter, more flexible units have to be involved.
Hence, in this work we show how by manipulation of the rigidity of the donor unit it is possible to find the trade-off between the properties of deep blue TADF emitters. Thus, here we present four derivatives of 9,9-dimethylthioxanthene-S,S-dioxide featuring 10,11-dihydro-5H-dibenz[b,f]azepine and diphenylamine donors attached in different fashion. Thorough photophysical investigation is provided. Theoretical approach is involved for better understanding of the observed results.
[1] J. Mater. Chem. C 2014, 2 (3), 421–424.
[2] Chem. Mater. 2015, 27 (19), 6675–6681.
[3] Chem. Mater. 2017, 29 (21), 9154–9161.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.