1. “I.G. Murgulescu” Institute of Physical Chemistry, Spl. Independentei, 202, Bucharest R-77208, Romania
2. University of Bucharest, Department of Chemistry, Bd. Republicii, 13, Bucharest R-70346, Romania
3. Università degli Studi, Dipartimento di Chimica, Laboratorio di Chimica Inorganica e Bioinorganica, Via Gino Capponi 7, Florence I-50121, Italy