Cyclic Triradicals Composed of Iminonitroxide-Gold(I) with Intramolecular Ferromagnetic Interactions.

A triangular gold(iminonitroxide-2-ide) trimer complex (5) was prepared and investigated to determine its magnetic properties. The results showed that the metalloid triradical is highly stable, even in solution under aerated conditions. The intramolecular exchange interaction of 5 was found to be positive (Jintra/kB≈+29 K), thus showing that 5 is in a quartet ground state. In addition, a silver sandwich complex (5-Ag+-5) was prepared and its electronic and magnetic properties were also clarified.