Magnetic properties of anion-radical salt [FeII(dipy)3](TCNQ)4·(CH3)2CO

Abstract Magnetic properties of anion-radical TCNQ salt [Fe(dipy) 3 ](TCNQ) 4 ·(CH 3 ) 2 CO have been investigated (dipy is 2,2′-dipyridil). X-ray diffraction data allow presence of two types of TCNQ stacks: tetramerized (diamagnetic) and partly dimerized (paramagnetic). Due to Mossbauer spectroscopy data iron cation appears as two-valent ion in low-spin state. Magnetic susceptibility temperature dependence is described by Bonner–Fischer model with additional weak impurity paramagnetism. Susceptibility curve is in good qualitative agreement with ESR spectra.