Circularly Polarized Room Temperature Red Phosphorescence from a [9]-Heterohelicene Diimide

13 September 2024, Version 1
This content is a preprint and has not undergone peer review at the time of posting.

Abstract

Circularly polarized room temperature phosphorescence (CP-RTP) in the red region is fascinating, however, challenging to achieve in organic molecules. The difficulty stems from two necessary conditions required to design such molecules. Firstly, achieving circularly polarized luminescence, with higher emission quantum yield in the longer wavelength region is challeng-ing. Secondly, attaining phosphorescence from such molecules under ambient conditions is difficult. Achieving both the cri-teria together in a single molecule is ambitious. In this work, we devise a novel design strategy to realize CP-RTP from a [9]-heterohelicene diimide. The designed molecule possesses helical chirality and an extended conjugation affording chiroptical responses in the red region. Interestingly a four-fold increment in the dissymmetry factor has been achieved by switching the solvent polarity. Furthermore, the incorporation of sulphur atom in the molecular framework facilitates a prolonged emis-sion lifetime of 1.09 ms under ambient conditions, making it the only example of a rylene diimide exhibiting CP-RTP.

Keywords

Circularly Polarized Phosphorescence
Room-temperature Phosphorescence
Red emission
Rylene diimides
heterohelicene

Supplementary materials

Title
Description
Actions
Title
Supporting Information
Description
Synthetic details, characterization data, optical investigations and computational details are provided.
Actions
Title
SCXRD
Description
.CIF file
Actions
Title
SCXRD
Description
.CIF file
Actions

Comments

Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.