Bonding and reactivity at oxide mineral surfaces from model aqueous complexes
Article Abstract:
It has been possible to determine the rates of oxygen exchange between an aqueous fluid and specific sites on the 'Al13' polyoxocation: AlO4Al12(OH)24(H2O)(super7+)(sub12). The structure of this polyoxocation is very similar to the surfaces of some Al-(hydr)oxide minerals in soils and catalyst supports. This research identified a very wide range of labilities for the different exposed oxy-groups on the model 'Al13' complex. It was shown that hydroxyl exchange takes place many times before any irreversible structural change that brings about complete dissociation.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 2000
User Contributions:
Comment about this article or add new information about this topic:
A better mousetrap
Article Abstract:
Dimitri A. Sverjensky and P.A Molling have provided a breakthrough in geochemical analysis by using linear free energy relations to correlate substituted crystalline solids with unsynthesizable ancient minerals and fluids. Using this technique, thermodynamic properties can be predicted for minerals and fluids that have so far escaped the grasp of geochemists. However, the correlations do not provide reaction mechanisms or metal-ligand interactions' associative or dissociative characters so empirical parameters should be used cautiously.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1992
User Contributions:
Comment about this article or add new information about this topic:
The mechanism of dissolution of oxide minerals
Article Abstract:
The difference between the protons added and removed in dissolution of oxide minerals rather than the number of protons required to form an activated complex gives the proton rate order. The mechanism explains similar values of the rate order and metal valence and the similarity between rates of water ligand lability in dissolved complexes and metal desorption. The assignment of ligand functional groups to metal-coordination sites indicates that ligand-promoted dissolution is often dependent on adsorbed proteins.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1996
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Avian nesting success in a selectively harvested north temperate deciduous forest. Effects of selective logging on forest bird populations in a fragmented landscape
- Abstracts: Human cerebellar activity reflecting an acquired internal model of a new tool. Internal model visualized
- Abstracts: Cheating as a mixed strategy in a simple model of aggressive communication. Assessment of expected performance and Zahavi's notion of signal
- Abstracts: Response to changes in food palatability in tufted capuchin monkeys, Cebus apella. Audience effects on food calls in captive brown capuchin monkeys, Cebus apella
- Abstracts: Direct measurement of electrical transport through DNA molecules. Room-temperature transistor based on a single carbon nanotube