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Journal of the Brazilian Chemical Society

versão impressa ISSN 0103-5053

Resumo

VAZ, Maria G. F. et al. Synthesis and Properties of New Molecule-Based Magnets Containing Mn(II), Cu(II) and Nitronyl Nitroxide Radical Cation. J. Braz. Chem. Soc. [online]. 2002, vol.13, n.2, pp. 183-189. ISSN 0103-5053.  http://dx.doi.org/10.1590/S0103-50532002000200009.

In this work, we describe the synthesis of two new copper(II) compounds, (Pr-Rad)2 [Cu(opba)].H2O (1) and (Bu-Rad)2[Cu(opba)].2H2O (2) where opba stands for ortho-phenylenebis(oxamato) and RRad+ are nitronyl nitroxide radical cations. From 1 and 2, two new molecule-based magnets [Pr-Rad]2[Mn2{Cu(opba)}3 ].3.3DMSO.5H2O (3) and [Bu-Rad]2 [Mn2{Cu(opba)}3].3DMSO.6H 2O (4) were obtained, respectively. The magnetic properties of precursors 1 and 2 show the presence of ferromagnetic interaction between the radical cations with copper(II), in the temperature range of 20-300 K. The magnets 3 and 4 exhibit spontaneous magnetization at critical temperatures, Tc, of 23 K and 24 K, respectively.

Palavras-chave : supramolecular chemistry; molecule-based magnets; molecular materials; catenanes; ferrimagnetism.

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