New Π-Donor-Acceptor Compounds Derived From a Macrocyclic Metal Complex

Abstract

Abstract The planar, macrocyclic metal complex niekel-1,4,8,11-tetraaza-5,7,12,14-tetramethyl(14)annulene [Ni(TATMA)] has been used as a π-donor to form new π-D·A compounds of the type [Ni(TATMA)]2A where A=TCNQ and NiS4C4H4. Magnetic susceptibility and conductivity measurements have been obtained for both compounds and the structure of the NiS4C4H4 derivative has been elucidated by x-ray diffraction methods. Both compounds are semiconductors with [sgrave]25o=10−4·10−3Ω−1cm−1 and Ea=0.1·0.25eV). The NiS4C4H4 derivative contains 1-D stacks of the π-donor which consist of metal-metal bonded [Ni(TATMA)+]2 dimers separated by uncharged Ni(TATMA) units. The NiS4C4H4 − ions are unstacked and presumably are responsible for the observed Curie-like spin susceptibility. Magnetic susceptibility measurements on the [Ni(TATMA)]2 TCNQ compound show no net spin susceptibility indicating either no net charge transfer in this case or an intermolecular association in the solid state involving both the Ni(TATMA)+ and TCNQ− ...