AI Article Synopsis
- Open-shell non-alternant polycyclic hydrocarbons (PHs) are gaining interest for their potential uses in areas like organic spintronics and quantum computing.
- Researchers synthesized three new cyclohepta[def]fluorene-based compounds with added benzo rings for stability, showing unique characteristics through various tests.
- These compounds demonstrate a narrow optical energy gap and exceptional stability, along with low singlet-triplet energy gaps, indicating possibilities for developing new materials with interesting properties for scientific applications.
Article Abstract
Open-shell non-alternant polycyclic hydrocarbons (PHs) are attracting increasing attention due to their promising applications in organic spintronics and quantum computing. Herein we report the synthesis of three cyclohepta[def]fluorene-based diradicaloids (1-3), by fusion of benzo rings on its periphery for the thermodynamic stabilization, as evidenced by multiple characterization techniques. Remarkably, all of them display a very narrow optical energy gap (E =0.52-0.69 eV) and persistent stability under ambient conditions (t =11.7-33.3 h). More importantly, this new type of diradicaloids possess a low-lying triplet state with an extremely small singlet-triplet energy gap, as low as 0.002 kcal mol , with a clear dependence on the molecular size. This family of compounds thus offers a new route to create non-alternant open-shell PHs with high-spin ground states, and opens up novel possibilities and insights into understanding the structure-property relationships.
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| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9324097 | PMC |
| http://dx.doi.org/10.1002/anie.202202170 | DOI Listing |
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