[1] Ecole Normale Super, Lab Biomol, Dept Chim, CNRS,UPMC,ENS,UMR 7203, F-75231 Paris 05, France
[2] Bruker BioSpin GmbH, D-76287 Rheinstetten, Germany
[3] CEA Saclay, Lab Struct & Dynam Resonance Magnet, CEA, CNRS,IRAMIS,DSM,SIS2M,UMR 3299, F-91191 Gif Sur Yvette, France
[4] Ecole Polytech Fed Lausanne, BCH, Inst Sci & Ingn Chim, CH-1015 Lausanne, Switzerland