FERROMAGNETIC SPIN COUPLING OF TERT-BUTYLNITROXIDE DIRADICALS THROUGHA CONJUGATED OLIGO(1,2-PHENYLENEVINYLENE)-COUPLER

Ferromagnetic spin coupling of the tert-butylnitroxide diradicals conn ected to the oligo(1,2-phenylenevinylene)-skeleton was studied to rela te with their pi-conjugated electronic structure. The spin coupling co nstant (J) determined from their magnetic susceptibility increased wit h the degree of oligomerization in the conjugated skeleton and was red uced in response to the conjugated but spacing phenylenevinylene unit. These 2J values qualitatively agreed with the semiempirically calcula ted ones.