Complex magnetism of ferrous chains based on alternating FeN4 and FeS4 tetrahedra

A combination of nuclear gamma resonance (Mossbauer effect) spectroscopy an d ac susceptometry are used to characterize polybis(1-methyl-2-thioimidazol ate)iron(II), [Fe(1-Me-2-S-imid)2]0.5Fe(Cp)(2) (hereafter I). An alternativ e explanation for the I's weak ferromagnetic ground stale, namely the alter nation of g values along the polymer chain, is qualitatively considered in the light of the ngr results, in particular the temperature dependence and limiting values of the quadrupole splittings of the paramagnetic tetrahedra l ferrous sites of this system. (C) 2001 Elsevier Science Ltd. All rights r eserved.