1. Section of Chemical Information Systems, University of Ulm, Albert Einstein Allee 47, 89081 Ulm, Germany
2. Department of Chemistry, Lomonosov Moscow State University, Moscow 119991, Russian Federation
3. Departamento de Química Física y Química Inorgánica, Facultad de Ciencias – I.U. CINQUIMA, Universidad de Valladolid, Paseo de Belén, 7, 47011 Valladolid, Spain