Magnetoresistance studies of the ferromagnetic molecular metal (BEDT-TTF)3[MnCr(C2O4)3] under pressure ☆

Abstract (BEDT-TTF) 3 [MnCr(C 2 O 4 ) 3 ] is the first ferromagnetic molecular metal, in which organic layers of BEDT-TTF alternate with infinite layers of the bimetallic oxalate complex [MnCr(C 2 O 4 ) 3 ] − . While the bimetallic layer undergoes a magnetic phase transition into a canted ferromagnetic state at 5.5 K, the metallic character of the conductivity is not affected by the magnetic transition [Nature 408 (2000) 447]. We performed magnetoresistance measurements ( B ≤17 T) at low temperatures ( T ≥900 mK) and under hydrostatic pressures of up to 2.0 GPa. Oscillations in the magnetoresistance develop under pressure that can be interpreted as Shubnikov–de Haas oscillations, if an internal magnetic field is taken into account. These measurements can thus be interpreted as a measure of the internal magnetic field in the conduction layer caused by the adjacent magnetic oxalate layers.