A magnetic organic conductor based on a π donor with a stable radical and a magnetic anion -: A step to magnetic organic metals with two kinds of localized spin systems

(TTP-PROXYL)FeCl4, where TTP-PROXYL is 2,5-bis(1,3-dithiol-2-ylidene)-1,3,4,6-tetrathiapentalene (TTP) incorporating the 2,2,5,5-tetramethyl-1-pyrrolidinyloxy (PROXYL) radical, is a semiconductor with two kinds of localized spin systems, that is, the systems of organic radical spins and 3d spins of magnetic FeCl4- ions. The 7 spin of the TTP-PROXYL radical cation disappears due to dimerization but the chi T-value of 4.65 Kemu mol(-1) indicates the coexistence of high-spin Fe3+ (S = 5/2) and PROXYL radical (S = 1/2) ill this salt. (TTP-PROXYL)GaCl4 is isostructural to the FeCl4 salt and exhibited similar semiconducting properties.