1. I. Physikalisches Institut, University of Cologne, Zülpicher Str. 77, 50937 Cologne, Germany
2. Institute of Spectroscopy, Russian Academy of Sciences, Fizicheskaya Str. 5, 142190 Troitsk, Moscow, Russia
3. Department of Optics and Spectroscopy, Tomsk State University, 36 Lenin av., 634050 Tomsk, Russia
4. Université de Grenoble Alpes, IPAG, F-38000 Grenoble, France
5. CNRS, IPAG, F-38000 Grenoble, France
6. Theoretical Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands