Thomas M. Baumann¹, Christoph Bostedt^5,8, Simon Dold¹, Gianluca Geloni¹, Markus Ilchen^1,9,10,11, Dooshaye Moonshiram⁴, Daniel Rolles¹², Artem Rudenko¹², Philipp Schmidt¹, Svitozar Serkez¹, Sergey Usenko¹, Ángel Martín Pendás¹³, Michael Meyer¹, Jesús González-Vázquez^2,‡, and Antonio Picón^2,3,4,§

• ¹European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
• ²Departamento de Química, Universidad Autónoma de Madrid, 28049 Madrid, Spain
• ³Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049, Madrid, Spain
• ⁴Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC), 28049, Madrid, Spain
• ⁵Laboratory for Ultrafast X-ray Sciences, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
• ⁶Laboratory of Theoretical Physical Chemistry, Institute of Chemical Sciences and Engineering, École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
• ⁷Department of Physics, Blackett Laboratory, Imperial College London, SW7 2AZ London, United Kingdom
• ⁸Paul-Scherrer Institute, CH-5232, Villigen PSI, Switzerland
• ⁹Institut für Experimentalphysik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
• ¹⁰Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
• ¹¹Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestrasse 85, 22607 Hamburg, Germany
• ¹²J.R. Macdonald Laboratory, Department of Physics, Kansas State University, Manhattan, Kansas 66506, USA
• ¹³Department of Analytical and Physical Chemistry, University of Oviedo, E-33006, Oviedo, Spain

• ^*These authors contributed equally to this work.
• ^†Contact author: daniel.rivas@xfel.eu
• ^‡Contact author: jesus.gonzalezv@uam.es
• ^§Contact author: antonio.picon@csic.es