Ferromagnetic coupling unit

Naturally, the product of two-electron reduction of the para derivative can be depicted (Scheme 3-54) as an anionic diborataquinoid system. In contrast with the para-dib-orataquinoid dianion, an anionic meta-quinoid system is impossible. Indeed, the meta-sub-stituted isomer depicted in Scheme 3-54 has been characterized as a spin-unpaired triplet species with boron-centered spins (Rajca et al. 1995). This dianion diradical can be viewed as two stable borane anion radicals linked with a ferromagnetic coupling unit, i.e., 1,3-phenylene see Chapter 1. 

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

Scheme 13. A schematic picture of a ferromagnetic coupling unit between two polaronic states aax>rding to the Fukotome model...

Murray et al. [218] synthesized a number of paramagnetic polymers containing an wi-phenylene unit as ferromagnetic coupling unit to ensure high spin interactions between spin-containing units. 

Sc—spin containing unit Fc—ferromagnetic coupling unit... 

C. Spin-containing Ferromagnetic coupling unit unit... 

C. The concept of the ferromagnetic coupling unit and several examples. 

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