Rigidly linked dinuclear platinum( ii ) complexes showing intense, excimer-like, near-infrared luminescence

Pander, Piotr; Walden, Melissa T.; Salthouse, Rebecca J.; Sil, Amit; Yufit, Dmitry S.; Dias, Fernando B.; Williams, J. A. Gareth

Abstract

Many luminescent platinum(ii) complexes undergo face-to-face interactions between neighbouring molecules, leading to bimolecular excited states that may emit at lower energy (dimers and/or excimers). Detailed photophysical studies are reported on dinuclear complexes, in which two NCN-coordinated Pt(ii) units are covalently linked by a xanthene such that intramolecular formation of such dimeric or excimeric states is possible. These complexes display strong excimer-like photoluminescence at low concentrations where their monometallic analogues do not. However, a striking difference emerges between complexes where the Pt(NCN) units are directly connected to the xanthene through the tridentate ligand (denoted Class a) and a new class of compounds reported here (Class b) in which the attachment is through a monodentate acetylide ligand. The former require a substantial geometrical rearrangement to move the metal centres of the Pt(NCN) units to a distance short enough to form excimer-like states. The latter require only a small deformation. Consequently, Class a compounds display negligible excimer-like emission in solid films, as the rigid environment hinders the requisite geometric rearrangement. Class b complexes, in contrast, display strong excimer-like emission in film, even at very low loadings. The new dinuclear molecular architecture may thus offer new opportunities in the quest for efficient NIR-emitting devices.

Citation

Pander, P., Walden, M. T., Salthouse, R. J., Sil, A., Yufit, D. S., Dias, F. B., & Williams, J. A. G. (2023). Rigidly linked dinuclear platinum( ii ) complexes showing intense, excimer-like, near-infrared luminescence. Journal of Materials Chemistry C Materials for optical and electronic devices, 11(43), 15335-15346. https://doi.org/10.1039/d3tc03432a

• Journal Article Type: Article
• Acceptance Date: Oct 16, 2023
• Online Publication Date: Oct 25, 2023
• Publication Date: Nov 21, 2023
• Deposit Date: Nov 10, 2023
• Publicly Available Date: Nov 10, 2023
• Journal: Journal of Materials Chemistry C
• Print ISSN: 2050-7526
• Electronic ISSN: 2050-7534
• Publisher: Royal Society of Chemistry
• Peer Reviewed: Peer Reviewed
• Volume: 11
• Issue: 43
• Pages: 15335-15346
• DOI: https://doi.org/10.1039/d3tc03432a
• Public URL: https://durham-repository.worktribe.com/output/1863159