Probing magnetic interactions in columnar phases of a paramagnetic gold dithiolene complex

International audienceA novel radical gold dithiolene complex exhibits a hexagonal columnar mesophase, as confirmed by optical microscopy , DSC analysis and X-ray diffraction . The extent of delocalization of the spin density in such a complex was analyzed by EPR . Temperature dependent magnetization measurements reveal that the global magnetic moment is remarkably affected at the liquid-crystalline phase transition with a marked hysteresis signature, rare behavior among the few described paramagnetic discotic phases. In addition, these molecules were found to strongly aggregate in solution into one-dimensional fibers with a mean diameter of 60 nm extending over micrometres, leading to the formation of gel-like structures. These fibers are stable and can be isolated on surfaces. The gelation of the system can also be detected by temperature-dependent magnetic measurements

A radical mixed-ligand gold bis(dithiolene) complex

International audienceA mixed-ligand bis(dithiolene) gold complex is isolated from scrambling reaction of two neutral radical symmetric complexes. Its asymmetric character translates into specific structural and electronic properties including larger electrochemical and optical band gaps than those of both precursors

Aza-beta3-Cyclotetrapeptides

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