Affiliation: | a LPMTM-CNRS, Institut Galilée, Université Paris Nord, 99, av. J.B. Clément, F-93430 Villetaneuse, France b Institute for Superhard Materials of the National Academy of Sciences of Ukraine, Kiev 04074, Ukraine c Hamburger Synchrotronstrahlungslabor (HASYLAB-DESY), D-22607 Hamburg, Germany |