The structure and speciation of bichromate, dichromate and chromate were studied to temperatures up to 400 degrees C using the combined information obtained from infra red (IR) and x-ray absorption fine structure (XAFS) spectroscopy. Actual species concentrations were obtained from the IR measurements, which were then used as fixed input parameters for the XAFS analysis. With this procedure a complete description of the molecular structure of each chromate species to high temperatures was obtained. In agreement with previous high temperature studies on the chromate systems, the bichromate species was found to become thermodynamically favored at high temperatures.
Revised: April 23, 2001 |
Published: March 15, 2001
Citation
Hoffmann M.M., J.G. Darab, and J.L. Fulton. 2001.An Infrared and X-ray Absorption Study of the Equilibria and Structures of Chromate, Bichromate and Dichromate in Ambient Aqueous Solutions.Journal of Physical Chemistry A 105.PNNL-SA-34192.