1. Department of Mathematics, Politecnico di Milano, Via E. Bonardi 9, 20133 Milano, Italy
2. Faculty of Mathematics, University of Vienna, Oskar-Morgenstern-Platz 1, A-1090 Vienna, Austria
3. Vienna Research Platform on Accelerating Photoreaction Discovery, University of Vienna, Währingerstraße 17, A-1090 Vienna, Austria
4. Istituto di Matematica Applicata e Tecnologie Informatiche “Enrico Magenes”, Via Ferrata 1, I-27100 Pavia, Italy