1. Department of Chemistry, University of Pavia, viale T. Taramelli 12, 27100 Pavia, Italy
2. INSTM, via G. Giusti 9, 50121 Florence, Italy
3. E4 Computer Engineering, via Martiri delle libertà 66, 42019 Scandiano (RE), Italy
4. Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Girona, Catalonia E-17071, Spain
5. ICREA, Barcelona, Catalonia E-08010, Spain
6. Centre for Computational Chemistry, School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K.