Syntheses, crystal structures, and physical properties of new cyanamides and carbodiimides of the magnetic 3d transition metals

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The general synthetic purpose of this project is to combine paramagnetic transition-metal atoms with a bidentate bridging ligand to form extended magnetic solid-state networks. In particular, new synthetic as well as structure-analytical results are sought for in the fields of extended cyanamide and carbodiimide compounds (incorporating NCN2- building blocks) of the magnetic 3d transition metals; the chemistry of these promising and thermodynamically unstable¿but inert¿solid-state materials is largely unknown but one may expect novel physical (magnetic) properties due to the presence of 3d electrons on the transition metals in combination with the electronic/chemical functionality of the NCN2- bidentate group. We will first extend our present synthetic experience using two recently developed routes to further discover new transition metal-cyanamides and carbodiimides, characterize them using X-ray and neutron diffraction methods, measure their magnetic and thermodynamic properties, and rationalize their compositions and properties by means of electronic-structure calculations of density-functional type. Cyanamides and carbodiimides of higher complexities containing either combinations of different transition metals or between rare-earth and transition metals will also be synthesized. In short, the exploratory synthesis of new NCN2- based materials of the 3d transition metals, their structure elucidation, magnetic and thermodynamic characterization and also electronic-structure calculation will greatly extend our basic knowledge of a new class of materials.