Accurate Ab-initio Soft X-ray Spectroscopy Simulation of Molecules: Method, Examples and Insight

Speaker:  Francesco Segatta, UNIBO

Program Description:
In this contribution, I will present results on soft X-ray spectroscopy simulation of organic molecules (ethylene, azobenzene, NADH, etc.) carried out in our group.

An ample body of spectroscopic techniques will be considered: from steady-state XANES and XPS, through their time-resolved counterparts, to some more advanced (and not yet experimentally available) techniques such as 2DCXS (two-dimensional coherent X-ray spectroscopy, i.e., the X-ray analogue of 2D electronic spectroscopy) and TRUECARS (transient redistribution of ultrafast electronic coherences in attosecond Raman signals, designed to track passage via conical intersections).

All the presented results are based on high quality quantum chemistry calculations within the framework of multiconfiguration wave function theory, whose peculiarities I will briefly overview. Comparison with experimental spectra (whenever available) will be carried out to demonstrate the simulation accuracy and get new physical/chemical insight. Eventually, I will show what we have learned about the information content the various techniques can provide, and highlight what systems/processes each technique is best suited for.

Francesco Segatta,1,* A. Nenov,1 F. Montorsi,1 S. Mukamel,2 M. Garavelli11 Dipartimento di Chimica Industriale “Toso Montanari”, University of Bologna, 40136 Bologna, Italy2 Department of Chemistry and Department of Physics & Astronomy, University of California, Irvine, California 92697-2025, United States