Unlike extensively studied diradicals linked by π‐conjugated systems, only a few studies have investigated weakly coupled diradicals linked by an sp³ carbon atom. Herein, we prepared pyrrolidin‐1‐oxyl–(nitronyl nitroxide)‐dyad 5 and pyrrolidin‐1‐oxyl–iminonitroxide‐dyad 6. From the observed temperature dependence of the magnetic susceptibility, 5 and 6 were determined to be in singlet ground states with 2J_intra/k_B=−35.2 K and −13.6 K, respectively. From these results and theoretical calculations of related diradicals, the spin‐polarization model counting the small spin density of the sp³ carbon atom could be used as a spin‐prediction model.

中文翻译：

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（吡咯烷-1-氧基）-（硝基亚硝基氧）/（亚硝基氧）-染料的合成及磁性

与广泛研究通过π共轭体系连接的双自由基不同，只有少数研究研究了通过sp ³碳原子连接的弱耦合双自由基。在这里，我们制备了吡咯烷-1-氧-（亚硝酰基硝基）-二联体5和吡咯烷-1-氧-亚硝基氧二联体6。根据所观察到的磁化率的温度依赖性，确定5和6处于单重基态，分别为2 J _intra / k _B = -35.2 K和-13.6K。从这些结果和相关双基的理论计算中，自旋极化模型计算了sp ³的小自旋密度 碳原子可用作自旋预测模型。