New polynucleating ligands and their metal complexes with spin crossover activity

• Applicant: Professorin Dr. Birgit Weber
• Subject Area: Inorganic Molecular Chemistry - Synthesis and Characterisation
• Term: from 2004 to 2009
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5430085

The subsidies should allow the synthesis and characterisation of new polynucleating ligands and their complexes based on the ligand system used in the research group of Professor Jäger. In frame of the project "Magnetmaterialien für Kommunikationstechnik und Sensorik auf Basis molekularer Koordinationsverbindungen" founded by the Freistaat Thüringen (1996 - 1999), a large number of mononuclear as well as some dinuclear iron, copper and cobalt complexes have been synthesised and magnetically characterised. Especially some of the mononuclear iron complexes showed interesting magnetic behaviour as spontaneous magnetisation at low temperatures, metamagnetism and various spin crossover phenomena. The obtained knowledge about the influence of pheripheral substituends on the equatorial ligand as well as the axial ligand on the strength of the ligand field and therefore on the magnetic properties of the metal centre is an excellent pool for purposeful synthesis of polynucleating ligands and their metal complexes. This complexes offer the possibility to investigate systems with ferro- or ferrimagnetic interactions between the metal centres as well as coupled spin crossover phenomena.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1137: Molecular Magnetism