Professor Stefan Grimme Department of Chemistry The University of Bonn Friday, February 14, 2020 - 11:15am Chemistry Building, Room 400 Mulliken Lecture The lecture deals with the calculation of various spectroscopic properties of molecules. Electron impact mass spectrometry, the automated simulation of infrared spectra for unknown compound identification, 1H-NMR spectra, as well as optical spectra and electronically excited states are considered. The examples shown either deal with large systems (e.g. full QM protein treatments) or involve huge structural ensembles of medium-sized drug-type molecules (for IR or NMR). Therefore, for the initial steps of the automated and robust spectroscopy calculations, a multi-level ansatz including low-cost quantum chemistry methods is employed. In particular the routine computation of EI-MS and NMR spectra is only possible with the recently developed GFN-xTB family of semi-empirical tight-binding methods.