Charge-Transfer Salts of Electron-Rich Diruthenium and Macrocyclic Tetraruthenium Complexes

• Applicant: Professor Dr. Rainer Winter
• Subject Area: Inorganic Molecular Chemistry - Synthesis and Characterisation
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 435877990

The aim of this project is the synthesis and detailed characterisation of dinuclear and macrocyclic tetraruthenium complexes with expanded, pi-conjugated linkers and of their charge transfer salts. These complexes are constructed such as to entail the structural and electronic prerequisites for generating electrically conductive charge transfer salts with pi-stacked structures when combinded with appropriate strong organic electron acceptors such as tetrahalogenated bezoquinones X4BQ or tetracyano-para-quinodimethanes TCNQ and F4TCNQ. In particular, we will investigate the resulting charge-transfer salts with respect to their ionicity (i. e. the fraction of positive / negative charge at the donor / acceptor) and their optical, electronic and magnetic properties. We will obtain detailed information as to the extent of charge transfer between the organometallic donor and the organic acceptor by analyzing the changes of the Ru(CO) vibrational energies of the ruthenium alkenyl donors and of the CO and CN stretching frequencies of the organic acceptor as well as by srutinizing the charge transfer bands in their electronic spectra and electronic paramagnetic resonance spectra. We will also address the important question of how the ionicities and structures of the charge transfer salts depend on the stoichiometric ratio of the donor and the acceptor and their intrinsic redox potentials.

• DFG Programme: Research Grants