Journal ArticleCharge transfer complexes possessing a ... DADA ... structure with both the donor, D, and acceptor, A, being S = 1/2 radicals may exhibit cooperative magnetic phenomena. The complex [Fe(C5Me5)2]+ [TCNQ]-. exhibits metamagnetic behavior. The similarly structured [TCNE]-. and [C4(CN)6]-. complexes are ferromagnets, whereas the [DDQ]-. salt is a paramagnet. The high temperature magnetic susceptibility obeys the Curie-Weiss expression with 0 = + 30, + 30, and + 3 for the [TCNE]-., [C4(CN)6]-., and [TCNQ]-. salts, respectively. The ferromagnetic [TCNE]-. salt exhibits zero field Zeeman split 57Fe Mossbauer spectra with an internal field of 425.6 kOe at 4.23 K. After reviewing the current papers discussing ferromagnetism in molecular (organic) compounds, a qualitative model consistent with the necessary bulk spin alignment required for a ferromagnet is presented
