2007 GSA Denver Annual Meeting (28–31 October 2007)

Paper No. 9
Presentation Time: 3:30 PM

ADVANCING EXPERIMENTALLY-BASED MODELS OF MINERAL-WATER INTERFACES


FITTS, Jeffrey P., Environmental Sciences Department, Brookhaven National Lab, PO 5000 Bldg 830, Upton, NY 11973, fitts@bnl.gov

Models describing mineral-water interfacial chemistry have undergone significant refinements as a result of the emergence of an array of interface-specific atomic- and molecular-level probes. These probes include surface x-ray scattering and spectroscopy, scanning tunneling microscopy and optical second harmonic generation spectroscopy. Experimentally-determined inputs to the most advanced models include geometries of adsorbates, lattice parameters of mineral surface layers, electronic states of surface atoms and site-specific proton balances. This talk will include selections from this developmental history in order to discuss limitations of current experimentally-based conceptions of mineral-water interfaces. One critical limitation is imposed by the lack of a geometric description of the surface proton.