High pressure x-ray absorption spectroscopy at lower energy in the dispersive mode: application to Ce and FePO4.

J.P. Itié (1) , F. Baudelet (1, 2) , A. Congeduti (1) , B. Couzinet (1) , F. Farges (3) , A. Polian (1)

1 IMPMC - Institut de minéralogie et de physique des milieux condensés
2 SSOLEIL - Synchrotron SOLEIL
3 Laboratoire des Géomatériaux

X-ray absorption spectroscopy (XAS) using a diamond anvil cell has been extended to lower energies (below 6 keV) thanks to smaller diamond anvils and to a new acquisition set-up on the energy dispersive x-ray absorption beamline of LURE. The valence change of Ce with pressure is followed at the LIII edge of cerium up to 8 GPa together with the bond length variation during the same experiment. The pressure induced coordination change around the Fe atom in FePO4 is determined at the Fe K edge through the pre-edge feature behaviour, the XANES modification and the Fe–O bond length increase.

J.P. Itié, F. Baudelet, A. Congeduti, B. Couzinet, F. Farges, et al.. High pressure x-ray absorption spectroscopy at lower energy in the dispersive mode: application to Ce and FePO4.. Journal of Physics: Condensed Matter, 2005, 17, pp.S883-S888. ⟨10.1088/0953-8984/17/11/018⟩. ⟨hal-00020255⟩