Search

Abstract: The temperature manipulation induces the aggregation of Ru2(CO3)4 3− paddle-wheel precursors and Mn2+ ions in lower temperature ~10°C forming layer structural complex, K[Mn(H2O)4Ru2(CO3)4]·5H2O (1). It composes of new negative layer {Mn(H2O)5Ru2(CO3)4} n n−, and magnetic exchanges between spin centers result in ordering below 3.8K. The observed critical temperature is like the previously reported 3D hetero-metallic carbonates H0.3K0.7Mn[Ru2(CO3)4](H2O)5.5, which demonstrates that it is independent of the interlayer connecting in such heterometallic complexes based on square-grid layer {Ru2(CO3)4} n 3n−. [Copyright &y& Elsevier]

Abstract: [{MnIII(OH)(H2O)}3SiW9O34]4− 1a, has been isolated from the reaction of Na9[β-SiW9O34H]·23H2O and [Mn3O(O2CMe)6(HIm)3](O2CMe) (Im=imidazole C3H4N2) in aqueous solution. The trimetal-substituted polyoxometalate (TMSP) 1 has been fully characterized by single-crystal X-ray diffraction, elemental analysis, thermogravimetric analysis, and infrared spectroscopy. This monomeric anion is composed of one trilacunary Keggin fragment A-α-SiW9O34 and three manganese ions encapsulated resulting in a triangular {Mn(OH)}3 6+ ring core. Experimental structural and magnetism aspects of the material are reported and discussed. [Copyright &y& Elsevier]