Simulating Time-resolved X-ray Spectroscopy: Progress and Challenges

The emergence of X-FELs has meant that our ability to probe ultrafast structural dynamics is becoming increasingly common. Importantly, the combined structural, electronic and spin information contained within X-ray spectroscopy offers new perspectives for understanding the correlated dynamics of these degrees of freedom within the femtosecond regime. However, the complex nature and high information content of this class of techniques means that detailed theoretical studies are often essential to provide a firm link between the spectroscopic observables and the underlying molecular structure and dynamics.

Herein I will present some recent work on intersystem crossing dynamics in transition metal complexes and discuss the potential insight that could be obtained from femtosecond X-ray studies. I will also present recent work on exploiting on-the-fly quantum dynamics simulations and machine learning approaches to reduce the computational expense of simulating time-resolved X-ray signals.

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(2015).