Synthesis and magnetic properties of Mn-12-Based single molecular magnets with benzene and pentafluorobenzene carboxylate ligands

• Published in: Journal of superconductivity and novel magnetism Vol. 24; no. 1-2; p. 855
• Main Authors: Zagaynova, Valeria, Makarova, Tatiana L., Spitsyna, N. G., Boukhvalov, D. W.
• Format: Journal Article
• Language: English
• Published: 2011
• Subjects: agnetic properties; Mn12; SMM
• ISSN: 1557-1939
• DOI: 10.1007/s10948-010-1030-3

We report on the synthesis and magnetic properties of Mn 12 -based single molecular magnets (SMMs) with benzene and pentafluorobenzene carboxylate ligands. The changes in ligand structure are shown to have a decisive effect on the magnetic properties of the complexes produced. The compound with benzene demonstrates an unusual magnetic behavior, namely, temperature dependencies of magnetization taken under the zero-field-cooled and field-cooled conditions are split below 10 K and furthermore remnant magnetization and coercive force remain nonzero in this temperature range. In contrast, the compound with pentafluorobenzene displays the customary signatures of the blocking temperature at 3 K. The effect of ligand substitution was theoretically studied within the local density approximation taking into account on-site Coloumb repulsion. Calculation results confirm that the electronic structure and the magnetic exchange interactions between different Mn atoms strongly depend on the type of ligand.