[Co(en)(3)][Fe(CN)(6)] center dot H2O and [Co(en)(3)][Fe(CN)(6)]: A dehydration process investigated by single crystal X-ray analysis, thermal analysis and Mossbauer spectroscopy

摘要

The complexes [Co(en)(3)][Fe(CN)(6)] center dot H2O (1) and [Co(en)(3)][Fe(CN)(6)] (2) (en = 1,2-diaminoethane) have been prepared and characterized by elemental analysis, single crystal X-ray analysis, TG/DSC analyses and Fe-57 Mossbauer spectroscopy. Single crystals of 1 have been prepared by recrystallization of compound 1 from a water solution, while crystals of complex 2 have been synthesized in the solid state by dynamic heating of 1 up to 150 degrees C. Both complexes exhibit ionic structures built up of [Co(en)(3)](3+) cations and [Fe(CN)(6)](3-) anions. The presence and/or absence of the crystal water molecule in the complexes has a strong influence on their thermal stability, the extent of hydrogen bonding in the crystal structures and on the symmetry of the iron(III) environments in the [Fe(CN)(6)](3-) anions, as determined by Fe-57 Mossbauer spectroscopy. (C) 2006 Elsevier Ltd. All rights reserved.