Intermolecular Proton Transfer in Solid Phase: A Rare Example of Crystal-to-Crystal Transformation from Hydroxo- to Oxo-Bridged Iron(III) Molecule-Based Magnet

Intermolecular proton transfer in solid phase from the hydroxo bridge to a water molecule occurs in a new mu-hydroxo iron(III) compound of formula {EtNH3[Fe2(ox)2Cl2(mu-OH)].2H2O}n leading to a still crystalline compound in which the mu-oxo bridge replaces the mu-hydroxo one. Both three-dimensional compounds exhibit magnetic ordering at Tc ca. 70 K due to a spin canting.