A Pressure Dependent Antiferromagnetism of AlPcF·(TCNE)_x Film

Abstract

Magnetic properties of fluoro-aluminum phthalocyanine (AlPcF) film doped with tetracyanoethylene (TCNE) are studied by ESR. A strong pressure dependence is observed: At 760 Torr an antiferromagnetic transition takes place at 175±3 K, while, in vacuum, no magnetic transition is observed. DC conductivity does not have any pressure dependence. An X-ray diffraction study indicates that a pressure dependence of interlayer distance inside the film is a structural origin of the pressure dependence of the magnetism. A resonance mechanism of a charge transfer between AlPcF cation radical (Remark: Graphics omitted.) and TCNE anion radical (Remark: Graphics omitted.) is proposed in order to explain an interchain magnetic coupling.