1. Institute of Problems of Chemical Physics, Russian Academy of Sciences, Institutskii prosp. 18, Chernogolovka, Moscow Region, 142432 Russia
2. Lomonosov State Academy of Fine Chemical Technology, Vernadskii prosp. 86, Moscow, 117571 Russia
3. Chemical Department, Moscow State University, Vorob'evy gory, Moscow, 119992 Russia
4. Institute of Atomic and Molecular Sciences, Academia Sinica, P. O. Box 23-166 Taipei, Taiwan 106, ROC