A ROOM-TEMPERATURE MOLECULAR ORGANIC BASED MAGNET

The reaction of bis(benzene)vanadium with tetracyanoethylene, TCNE, affords an insoluble amorphous black solid that exhibits field-dependent magnetization and hysteresis at room temperature. The critical temperature could not be estimated as it exceeds 350 kelvin, the thermal decomposition temperature of the sample. The empirical composition of the reported material is V(TCNE)x-Y(CH2Cl2) with x approximately 2 and Y approximately 1/2. On the basis of the available magnetic and infrared data, three-dimensional antiferromagnetic exchange of the donor and acceptor spins resulting in ferrimagnetic behavior appears to be the mode of magnetic coupling.