Quantum mechanics builds large-scale graphs (networks): the vertices are the discrete energy levels the quantum system possesses, while the edges are the (quantum-mechanically allowed) transitions. Parts of the complete quantum mechanical networks can be probed experimentally via high-resolution, energy-resolved spectroscopic techniques, while the complete rovibronic line list information for a given molecule can only be obtained through sophisticated quantum-chemical computations. Experiments as well as computations yield what we call spectroscopic networks (SN). First-principles SNs of even small, 3- to 5-atomic molecules can be huge, including billions of transitions and millions of enery levels. Besides helping to interpret high-resolution spectra, the network-theoretical view offers several ideas for improving the accuracy and robustness of the increasingly important information systems containing line-by-line spectroscopic data. A present-day application of spectroscopic networks is within the MARVEL (Measured Active Rotational-Vibrational Energy Levels) approach, whereby the transitions information of a measured SN is turned into experimental energy levels via a weighted linear least-squares refinement.
2016. 09. 30. 10:15
BME Fizikai Intézet, Elméleti Fizika Tanszék, Budafoki út 8. F-épület, III lépcsőház, szemináriumi szoba
Attila Császár (ELTE Dept. Phys. Chem.)