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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Crystal water molecules as magnetic tuners in molecular metamagnets exhibiting antiferro-ferro-paramagnetic
Radovan Herchel1, Jiří Tuček, Zdeněk Trávníček
1Department of Inorganic Chemistry, Faculty of Science, Palacky University in Olomouc, 17 Listopadu 12, 771 46 Olomouc, Czech Republic. radovan.herchel@upol.cz
Abstract:
We studied the effects of the number of crystal water molecules on the magnetic behavior of {[Ni(en)(2)](3)[Fe(CN)(6)](2)·xH(2)O}(n) (1-3) (where en = ethylenediamine and x = 3, 2, or 0) coordination polymers by (57)Fe Mössbauer spectroscopy, single-crystal X-ray diffraction, and magnetization measurements. Magnetic phase diagrams constructed for all three compounds indicate that they behave as metamagnets exhibiting very rare field-induced antiferro-ferro-paramagnetic transitions. The number of crystal water molecules has a major effect on the Néel temperature, critical field, and magnetic hardness of the compounds in the ferromagnetic state. Moreover, the systems behave as molecular magnetic sponges, changing their magnetic properties due to the controllable and reversible dehydration/hydration process.
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