1. Kemisk Institut, Syddansk Universitet, Campusvej 55, 5230 Odense M, Denmark, Wydział Chemii, Uniwersytet Wrocławski, ul. F. Joliot-Curie 14, 50383 Wrocław, Poland, School of Chemistry, Queen's University of Belfast, Stranmillis Road, Belfast BT9 5AG, Northern Ireland, and Département de chimie physique, Université de Genève, 30 quai Ernest-Ansermet, 1211 Genève 4, Switzerland