Ultrafast monitoring and synthetic control of electronic properties of a self-assembled coordination system as a multi-site luminescent probe for sensoric and imaging applications

• Applicants: Professor Dr. Bernd Abel; Professor Dr. Berthold Kersting
• Subject Area: Inorganic Molecular Chemistry - Synthesis and Characterisation ; Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
• Term: from 2018 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 404530043

The present approach aims at a novel strategy to develop molecular fluorescent probes with more than one site for molecular or ion recognition. We propose a novel design concept for a multi-site fluorescence probe that enables a multiplex or logic system response or the control and switching of sensor features, much beyond those observed in conventional molecular probes, requiring advanced synthesis guided by ultrafast spectroscopy and theory. The target compounds, constructed in a modular approach by metal-templated Schiff-base reactions, contain two selective binding sites, which constitute an integral part of a central salicyclidene-aldimine chromophore unit. Transition metal binding (Zn2+, Cu+) at site A enhances the fluorescence, while occupation of site B (Li+, Na+, K+) modulates the fluorescence properties. The system responses are monitored with photoelectron emission spectroscopy from liquid and solid interfaces, continuum probe transient absorption and fluorescence lifetime imaging and the data are interpreted employing density functional theory providing the guidelines for selective synthetic improvements.

• DFG Programme: Priority Programmes
• Subproject of: SPP 2102: Light Controlled Reactivity of Metal Complexes