Strong antiferromagnetic interactions in charge-transfer salts of mixed cyclopentadienyudimolene complexes of MO/sup (IV)/.

Summary form only given. Mixed cyclopentadienylldithiolene complexes of general formula C/sub P2/M/sup (IV)(dithiolene), (M: Ti, Nb, Mo; dithiolene: dmit, dddt) have been prepared and electrochemically characterized. While the d/supO/ titanium complexes do not support any reversible oxidation, their d/sup 1/ Nb and d/sup 2/ Mo analogs are reversibly oxidized. Cation-radical salts and charge-transfer salts of the latter have been prepared. They all exhibit strong antiferromagnetic interactions, which eventually condense in a three dimensionnal antiferromagnetic ground-state in a series of cation-radical salts of C/sub P2/MO(dmit), as characterized by AFMR. Correlations between the geometries of the neutral and oxidized species and the electronic structure of the various dithiolene ligands are revealed by EH calculations. This discussion is extended to related anionic complexes of general formula CpM/sup(IV)/(dithiolene)/sub 2-/, M: Ti, Mo, whose structural and electronic properties are also Aescribed.