Optical spectra of silicon-bearing clusters and nanostructures of astrophysical interest

• Applicant: Professor Dr. Otto Dopfer
• Subject Area: Astrophysics and Astronomy
• Term: since 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 431702392

We propose to determine the structural and electronic properties of small silicon-bearing clusters and nanostructures, especially those of astrophysical relevance, by means of vibrational and optical laser spectroscopy and quantum chemical calculations. The chemical evolution from small silicon oxides, silicates, and related molecules to large micrometer-sized silicate dust particles in the interstellar medium is poorly understood. Intermediates between these size regimes must exist but are elusive to observations. Laboratory optical spectra of these species are virtually unavailable in the literature. The purpose of this project is to fill this gap by determining the optical and photochemical properties, stabilities, photofragmentation patterns, and chemical reactivity of these species. The results may not only enable the astronomical detection of those particles but also provide valuable input to theoretical models of circumstellar dust shells. While we concentrate herein on the astrophysical context of silicon oxides, silicates, and related molecules, the species under investigation are also of interest in other fields, such as semiconductor and materials sciences and nanophotonics. The optical properties of these species are also of general interest with respect to developing, improving, and testing quantum chemical approaches that enable the reliable prediction of the involved excited states, which has remained a challenging field in quantum chemistry.

• DFG Programme: Research Grants
• Co-Investigator: Dr. Marko Förstel