1. Laboratory of Quantum Chemistry, Irkutsk State University, 664003 Irkutsk, Russia, Favorsky Institute of Chemistry, SB RAS, 664033 Irkutsk, Russia, Theoretische Chemie, Physikalisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 229, D-69120 Heidelberg, Germany, Sincrotrone Trieste, in Area Science Park, I-34149 Basovizza (Trieste), Italy, CNR-IMIP, c/o GasPhase@Elettra (Trieste), Montelibretti (Rome), I-00016 Italy, and Laboratorio Nazionale TASC, INFM-CNR, 34149 Trieste, Italy