To gain a more fundamental understanding of abiotic processes controlling reduction reactions of aqueous chromate and dichromate ions (Cr(VI)aq) in subsurface environments, we carried out molecular-level experimental and modeling studies of the interaction of water and Cr(VI)aq with well-characterized single crystal samples of synthetic and natural hematite and magnetite. A reductionist approach was adopted in which simplified model systems of increasing complexity were studied. Photoemission spectroscopy (PES), photo-electron diffraction, and vacuum STM were used to characterize the composition, atomic structure, and morpho-logy of clean surfaces of ?-Fe2O3(0001) and Fe3O4(100) grown by molecular beam epitaxy on single crystal substrates of ?-Al2O3(0001) and MgO(100), respectively.
Revised: January 5, 2007 |
Published: May 1, 2000
Citation
Brown G.E., S.A. Chambers, J.E. Amonette, J.R. Rustad, T. Kendelewicz, P. Liu, and C.S. Doyle, et al. 2000.Interaction of Aqueous Chromium Ions with Iron Oxide Surfaces. In Nuclear Site Remediation: First Accomplishments of the Environmental Management Science Program. ACS Symposium Series, edited by Eller, P. Gary; Heineman, William R. 212-246. Washington Dc:American Chemical Society.PNNL-SA-43343.