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Title: Calculation of Water-Exchange Rates on Aqueous Polynuclear Clusters and at Oxide-Water Interfaces.

Abstract

The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. The rates of a wide variety of reactions in aqueous coordination compounds can be correlated with lifetimes of water molecules in the inner-coordination shell of the metal. For simple octahedral metal ions, these lifetimes span ~10²⁰ but are unknown, and experimentally inaccessible, for reactive sites in interfacial environments. Using recent data on nanometer-sized aqueous aluminum clusters, we show that lifetimes can be calculated from reactiveflux molecular dynamics simulations. Rates scale with the calculated metal-water bond lengths. Surprisingly, on all aluminum(III) mineral surface sites investigated, waters have lifetimes in the range of 10⁻⁸-10⁻power10 s, making the surface sites as fast as the most reactive ions in the solution.

Authors:
; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
921414
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Inorganic Chemistry, 46(8):2962-2964; Journal Volume: 46; Journal Issue: 8
Country of Publication:
United States
Language:
English
Subject:
58 GEOSCIENCES; ALUMINIUM OXIDES; WATER; INTERFACES; MOLECULAR CLUSTERS; LIFETIME; MOLECULAR DYNAMICS METHOD; BOND LENGTHS; OXIDE MINERALS; Environmental Molecular Sciences Laboratory

Citation Formats

Wang, Jianwei, Rustad, James R., and Casey, William H.. Calculation of Water-Exchange Rates on Aqueous Polynuclear Clusters and at Oxide-Water Interfaces.. United States: N. p., 2007. Web. doi:10.1021/ic070079+.
Wang, Jianwei, Rustad, James R., & Casey, William H.. Calculation of Water-Exchange Rates on Aqueous Polynuclear Clusters and at Oxide-Water Interfaces.. United States. doi:10.1021/ic070079+.
Wang, Jianwei, Rustad, James R., and Casey, William H.. Tue . "Calculation of Water-Exchange Rates on Aqueous Polynuclear Clusters and at Oxide-Water Interfaces.". United States. doi:10.1021/ic070079+.
@article{osti_921414,
title = {Calculation of Water-Exchange Rates on Aqueous Polynuclear Clusters and at Oxide-Water Interfaces.},
author = {Wang, Jianwei and Rustad, James R. and Casey, William H.},
abstractNote = {The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. The rates of a wide variety of reactions in aqueous coordination compounds can be correlated with lifetimes of water molecules in the inner-coordination shell of the metal. For simple octahedral metal ions, these lifetimes span ~10²⁰ but are unknown, and experimentally inaccessible, for reactive sites in interfacial environments. Using recent data on nanometer-sized aqueous aluminum clusters, we show that lifetimes can be calculated from reactiveflux molecular dynamics simulations. Rates scale with the calculated metal-water bond lengths. Surprisingly, on all aluminum(III) mineral surface sites investigated, waters have lifetimes in the range of 10⁻⁸-10⁻power10 s, making the surface sites as fast as the most reactive ions in the solution.},
doi = {10.1021/ic070079+},
journal = {Inorganic Chemistry, 46(8):2962-2964},
number = 8,
volume = 46,
place = {United States},
year = {Tue Apr 17 00:00:00 EDT 2007},
month = {Tue Apr 17 00:00:00 EDT 2007}
}
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