Magnetic susceptibility of α and β phases of di[bis(ethylenediothiolo)tetrathiafulvalene] tri-iodide [(BEDT−TTF)2I3] under pressure

We report static magnetic susceptibility data, χ(T), for the α and β phases of the organic conductor di[bis(ethylenediothiolo)tetrathiafulvalene] tri-iodide [(BEDT−TTF)2I3] both at ambient pressure and under applied pressures of up to 10 kbar. Ambient pressure ESR data for both phases below 300 K are also presented. The temperature dependence of the spin susceptibility χβs(T) for the superconductor β-(BEDT−TTF)2 I3 is unusually small for organic conductors; the pressure derivative ∂lnχβs∂P is found to be only moderate in magnitude (-3.3% per kbar) and independent of temperature below 300 K. For the αq phase, ∂lnχαs∂P≃−2.0%Kbar at ambient temperature