1. Herzen State Pedagogical University of Russia, Department of Chemistry, Moyka 48, St. Petersburg, Russia, 191186, ISOF-CNR (sez.Ferrara), Dipartimento di Chimica, Università di Ferrara, via L.Borsari, 46, 44100 Ferrara, Italy, and University of Northern Iowa, Department of Chemistry, MSH, Cedar Falls, Iowa 50614