Magnetic properties, 1,2-dithiolenes

The solid-state conducting and magnetic properties of 1,2-dithiolene and... 

Keywords M(dmit)2, Metal bis(dithiolene), Metallocenium, Radical cations, Spin crossover, Magnetic properties, Superconductor... 

The first metal bis-dithiolene complex with an SCO moiety as counter-ion was reported in 2005 [99], namely [Fe(sal2-trien)][Ni(dmit)2] (Fig. 8). Usually, [Fe(sal2-trien)]+ is a Fera complex which exhibits very modest magnetic properties a gradual and incomplete spin transition is observed when it is combined with (PF6) and (BPI14), and the complex remains in the LS state with Cl-, I-and (NO3)-. 

Magnetic Properties of Radical, Crystalline Mixed Cyclopentadienyl/Dithiolene Complexes... 

As mentioned above, complexes with different Cp/dithiolene ratio have been described in the literature. They will be described successively below, with specific attention to the paramagnetic species available for the investigation of their solid state magnetic properties. 

The calculations also bring to light a significant U ( = ) interaction between the metal center and the C=C bond of the endo dithiolene ligand in the U(V) anionic complex, which does not exist in the dianionic species. Again, magnetic properties of these air-sensitive compounds were not investigated. 

Dithiolenes have been the subject of numerous studies relating to their ability to conduct electric currents and to show unusual magnetic properties. Both are consequences of extended inter-molecular interactions in molecular crystals of such order that the overlap between adjacent molecules is strong and uniform throughout the entire crystal. 

The magnetic properties and the magnitude of the electrical conductivity thus largely depend on the stacking arrangements in dithiolenes in nonintegral oxidation states. Many structural investigations concern these questions. 

Finally, in addition to Sections II (electrical properties), III (magnetic properties), and IV (optical properties), Section V will be devoted to dithiolene complexes exhibiting coexisting or coupled properties (electrical and magnetic, or electrical and optical). 

In Section III, we also discussed the spin-ladder behavior of dithiolene complex-based compounds, namely, (p-EPYNN) Ni(dmit)2], (DT-TTF)2-[Au(mnt)2], and [Cp2M(dmid)](TCNQF4). All of these compounds display semiconducting behavior and no interplay of electrical and magnetic properties was reported. 

Likewise, the first dithiolene complex-based magnet, (Cp2Mn)[Ni(dmit)2] (350), is a semiconductor, as could be expected from its stoichiometry, and the magnetic properties of further oxidized conducting species (CpjMn fN dmiQJ remain to be determined (531). 

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