J. Phys. IV France 7 (1997) C2-1167-C2-1168
Structural Characterization of Intercalated C2Fx Compounds Using XAFS Polarization DependenciesN.V. Bausk, S.B. Erenburg, N.F. Yudanov and L.N. Mazalov
Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Lavrentiev ave 3, Novosibirsk 630090, Russia
Orientation dependencies of FeK, BrK EXAFS and XANES spectra have been measured for intercalated compounds of the composition C2Fx*yA (X≈1, A=Br2, BrF3, Fe(AA)3, FeCl3) synthesized by diffusion from solutions. An approach has been developed which allows determination of the ranges of the orientation angles of T-shaped BrF3 molecules from XANES spectra. The values of the orientation angles of BrF3 molecules were determined by simultaneously analyzing EXAFS and XANES data. It was found that heating leads to the formation in the intercalated compound of lens-like regions containing oriented BrF3 molecules. The orientation and geometry of Br2 molecules in the studied compounds were shown to be substantially different from those in graphite intercalation compounds. The intercalation was shown to lead to deformation of the Fe(AA)3 molecule while the FeCl3 molecules form dimers.
© EDP Sciences 1997