Spin coupling in radicals

Similarly, a polyradical might be viewed as many unpaired electrons coupled through spin-coupling units with different coupling constants. 

Since m-phenylene (90) is a ferromagnetic coupling unit, radicals 91-93 all 

Energy gaps between the ground and lowest excited states and coupling constants through m- 

8 The ratio of coupling constants between polyradicals and diradical is also listed for comparison. bThe coupling constant through the central m-phenylene is given. 

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