[1] Ecole Mines, Sci & Genie Mat Met Lab, CNRS, UMR 7584, F-54042 Nancy, France
[2] Univ Nancy 1, CNRS, UMR 7565, F-54056 Vandoeuvre Les Nancy, France
[3] Univ Nancy 1, Serv Commun Microscopie Elect Transmiss, F-54056 Vandoeuvre Les Nancy, France
[4] Univ Nancy 1, Inst Natl Polytech Lorraine, Lab Phys Solide, CNRS,UMR 7556, F-54056 Vandoeuvre Les Nancy, France
[5] Univ Paris 06, Lab Chim Phys Mat & Rayonnement, CNRS, UMR 7614, F-75231 Paris 5, France