| Autor: |
Chengfang Shi, Laiwei Gao, Martin Baumgarten, Dongdong Wei, Zhipeng Xu, Wenping Wang, Di Wang |
| Jazyk: |
angličtina |
| Rok vydání: |
2023 |
| Předmět: |
|
| Zdroj: |
Magnetochemistry, Vol 9, Iss 7, p 178 (2023) |
| Druh dokumentu: |
article |
| ISSN: |
2312-7481 |
| DOI: |
10.3390/magnetochemistry9070178 |
| Popis: |
In contrast to diradical linked by π-conjugation, there have been only a limited number of studies reported for those linked by homoconjugation systems. Bis(nitronyl nitroxide) diradicals and monoradical connected by a core non-rigid triptycene unit were synthesized. EPR spectroscopy and SQUID were employed to investigate the magnetic exchange interactions. The results demonstrate that the values of ΔEST are 0.19 kcal/mol (J = 34.4 cm−1) for 2,6-TP-NN and −0.21 kcal/mol (J = −36.9 cm−1) for 2,7-TP-NN, indicating ferromagnetic interaction and antiferromagnetic interaction, respectively. The spin polarization rule is not a precise predictor of the behavior of triptycene diradicals, and therefore, we improve the model. The experimental findings indicate that homoconjugation can function directly as a coupling pathway between the two spin centers, which is in qualitative agreement with the DFT theoretical calculations and the Borden rule. This research has found a special means of achieving spin coupling in non-rigid aromatics by means of homoconjugation. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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