Intramolecular Magnetic Interaction of Spin-Delocalized Neutral Radicals through m-Phenylene Spacers
Intramolecular Magnetic Interaction of Spin-Delocalized Neutral Radicals through m-Phenylene Spacers
复制标题
自旋离域中性自由基通过间亚苯基间隔基的分子内磁相互作用
作者：
Murata;T.; Asakura;N.; Ukai;S.; Ueda;A.; Kanzaki;Y.; Sato;K.; Takui;T.; Morita;Y.
合成了一种新的双自由基，它含有两个通过间亚苯基连接的4，8，10-三氧代三角烯（TOT）中性自由基单元，并通过ESR测量进行了表征.电化学研究表明，双自由基经过两次单电子还原生成相应的二价阴离子，表明两个TOT单元之间通过π共轭间隔基发生电子相互作用.与单体相比，两个TOT单元之间的强分子内相互作用产生了自旋投射的小超精细耦合。温度依赖的ESR测量表明，该二聚体在基态表现为S =1的物种，铁磁相互作用为2 J/kB=+7 3 K.
A new diradical having two 4,8,10‐trioxotriangulene (TOT) neutral radical units linked through anm‐phenylene moiety was synthesized and characterized by ESR measurements. An electrochemical study showed that the diradical undergoes two one‐electron reductions to generate corresponding dianion species, suggesting the electronic interaction between twoTOTunits through the π‐conjugated spacer. A strong intramolecular interaction between the twoTOTunits gives rise to the spin‐projected small hyperfine couplings in comparison with those of the monomer. Furthermore, the temperature dependent ESR measurement revealed that the dimer behaves as anS=1 species in the ground state with a ferromagnetic interaction of 2J/kB=+7±3 K.