Abstract By attaching pyridine groups to a diaza[6]helicene, a helical, bis‐ditopic, bis‐N N‐coordinating ligand can be accessed. Dinuclear rhenium complexes featuring this bridging ligand, of the form [{Re(CO)3Cl}2(N N−N N)], have been prepared and resolved to give enantiopure complexes. These complexes are phosphorescent in solution at room temperature under one‐ and two‐photon excitation. Their experimental chiroptical properties (optical rotation, electronic circular dichroism and circularly polarized emission) have been measured. They show, for instance, emission dissymmetry factors of c.a. ±3x10−3. Quantum‐chemical calculations indicate the importance of stereochemistry on the optical activity, pointing towards further design improvements in such types of complexes. 
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                            Predicting Emission Spectra of Heteroleptic Iridium Complexes Using Artificial Chemical Intelligence
                        
                    
    
            Abstract We report a deep learning‐based approach to accurately predict the emission spectra of phosphorescent heteroleptic [Ir(C6N)2(N^N)]+complexes, enabling the rapid discovery of novel Ir(III) chromophores for diverse applications including organic light‐emitting diodes and solar fuel cells. The deep learning models utilize graph neural networks and other chemical features in architectures that reflect the inherent structure of the heteroleptic complexes, composed of C^N and N^N ligands, and are thus geared towards efficient training over the dataset. By leveraging experimental emission data, our models reliably predict the full emission spectra of these complexes across various emission profiles, surpassing the accuracy of conventional DFT and correlated wavefunction methods, while simultaneously achieving robustness to the presence of imperfect (noisy, low‐quality) training spectra. We showcase the potential applications for these and related models forin silicoprediction of complexes with tailored emission properties, as well as in “design of experiment” contexts to reduce the synthetic burden of high‐throughput screening. In the latter case, we demonstrate that the models allow us to exploit a limited amount of experimental data to explore a wide range of chemical space, thus leveraging a modest synthetic effort. 
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                            - Award ID(s):
- 1954262
- PAR ID:
- 10527643
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- ChemPhysChem
- ISSN:
- 1439-4235
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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