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arXiv · 2207.01290

Resolving Vibrations in a Polyatomic Molecule with Femtometer Precision

Patrick Rupprecht·Lennart Aufleger·Simon Heinze·Alexander Magunia·Thomas Ding·Marc Rebholz·Stefano Amberg·Nikola Mollov·Felix Henrich·Maurits W. Haverkort·Christian Ott·Thomas Pfeifer
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Abstract

We measure molecular vibrations with femtometer precision using time-resolved x-ray absorption spectroscopy. For a demonstration, a Raman process excites the A$_{1g}$ mode in gas-phase SF$_6$ molecules with an amplitude of $\approx50$ fm, which is probed by a time-delayed soft x-ray pulse at the sulfur $L_{2,3}$-edge. Mapping the extremely small measured energy shifts to internuclear distances requires an understanding of the electronic contributions provided by a many-body ab initio simulation. Our study establishes core-level spectroscopy as a precision tool for time-dependent molecular-structure metrology.

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Patrick Rupprecht, Lennart Aufleger, Simon Heinze, Alexander Magunia, Thomas Ding, Marc Rebholz, Stefano Amberg, Nikola Mollov, Felix Henrich, Maurits W. Haverkort, Christian Ott, Thomas Pfeifer. 2022-07-04. Resolving Vibrations in a Polyatomic Molecule with Femtometer Precision. https://arxiv.org/abs/2207.01290

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