Siloxanes, alumoxanes and alumosiloxanes as models for surface defects in hydrolysis and condensation reactions (A01)

• Subject Area: Inorganic Molecular Chemistry - Synthesis and Characterisation
• Term: from 2014 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 234149247

Subject of the project is to study hydrolysis and condensation processes at strained siloxane, alumoxane and alumosiloxane compounds. The latter can be considered to be model compounds for defect struc¬tures at silicate or aluminosilicate surfaces. They will be prepared by oxygenation of subvalent Si, Al and Al/Si compounds. Conceivable target structures are edge-sharing siloxane and alumosiloxane tetrahedra, peroxido or superoxido moieties and Al-O-Al linkages. We aim to monitor hydrolysis or condensation reactions and to identify larger cluster by mass spectrometry and NMR as well as by IR and Raman spectroscopy. It is also envisaged to stabilise intermediates and incipient structures by hydrogen bonding.

• DFG Programme: Collaborative Research Centres
• Subproject of: SFB 1109: Understanding of Oxide/Water Systems at the Molecular Scale: Structural Evolution, Interfaces and Dissolution
• Major Instrumentation: NMR probehead
• Instrumentation Group: 1790 Spektrometer (Massen-, NMR-, außer 170-178)
• Applicant Institution: Humboldt-Universität zu Berlin
• Project Head: Professor Dr. Thomas Braun