Antiferromagnetism of Iodine Doped AlPcF Film Deposited on KCl

The magnetism of iodine doped fluoro-aluminum phthalocyanine (AlPcF-I0.1) film deposited on KC1 (100) surface is studied by electron spin resonance (ESR) spectroscopy. An X-ray diffraction study indicates that two distinct phases coexist in the film : In one phase, the AlPcF chains lay parallel to the film plane, and, in the other phase, align perpendicular to the film plane. Both phases exhibit an antiferromagnetic transition at Tc=195±15 K under the pressure of 1 atm, while, at 0 atm, no magnetic transition takes place above 80 K. The g value does not depend on the pressure significantly, indicating that the back charge transfer probability α2 between AlPcF and I3 − does not have any correlation with Tc.