1. Department of Physical and Chemical Sciences, University of L’Aquila, L’Aquila 67010, Italy
2. Department of Chemical Sciences, University of Padova, Padova 35131, Italy
3. Department of Physics, Informatics and Mathematics, University of Modena and Reggio Emilia, Modena 41125, Italy
4. Instituto de Cibernética, Matemática y Física (ICIMAF), La Habana 10400, Cuba
5. Department of Physics, University of Milano, Milano 20133, Italy