Magnetic resonance analysis of the phase transition in fluoranthene radical cation salts

Abstract

EST-T 1, -T 2 and -linewidth were measured for the quasi onedimensional organic conductor (FA) 2PF 6 in its low-temperature “semiconducting” phase, for Larmor frequencies between 100 MHz and 9.5 GHz. From analysis of the pronounced temperature- and orientation-dependences, originating from intrastack magnetic dipole-dipole interaction, we derive that with decreasing temperature the thermally activated spins become increasingly correlated.