* Corresponding authors

^a Department of Chemistry, KU Leuven, Celestijnenlaan 200F (PO box 2404), 3001 Heverlee, Belgium
E-mail: karel.goossens@chem.kuleuven.be
Fax: +32 16 327992
Tel: +32 16 327431

^b Department of Chemistry, University of York, Heslington, York, United Kingdom

^c f-Element Coordination Chemistry Laboratory, Department of Inorganic and Physical Chemistry, Ghent University, Krijgslaan 281 – building S3, 9000 Gent, Belgium

^d Institute for Nuclear Materials Sciences (SCK·CEN), Boeretang 200, 2400 Mol, Belgium
E-mail: thomas.cardinaels@sckcen.be
Fax: +32 14 321216
Tel: +32 14 333185