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Title: Large Continuous Mechanical Gradient Formation via Metal-Ligand Interactions

Authors:
 [1];  [1];  [2];  [1];  [3];  [3];  [1]
  1. Department of Chemistry, University of California, Irvine, 1102 Natural Sciences 2 Irvine CA 92697 USA
  2. Nanovea, 6 Morgan Ste 156 Irvine CA 92618 USA
  3. Department of Chemical Engineering and Materials Science, University of California, Irvine, Irvine CA 92697 USA
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1407836
Grant/Contract Number:
FG02- 04ER46162
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Angewandte Chemie (International Edition)
Additional Journal Information:
Journal Name: Angewandte Chemie (International Edition); Journal Volume: 56; Journal Issue: 49; Related Information: CHORUS Timestamp: 2017-12-01 08:58:26; Journal ID: ISSN 1433-7851
Publisher:
Wiley Blackwell (John Wiley & Sons)
Country of Publication:
Germany
Language:
English

Citation Formats

Neal, James A., Oldenhuis, Nathan J., Novitsky, Andrea L., Samson, Emil M., Thrift, William J., Ragan, Regina, and Guan, Zhibin. Large Continuous Mechanical Gradient Formation via Metal-Ligand Interactions. Germany: N. p., 2017. Web. doi:10.1002/anie.201707587.
Neal, James A., Oldenhuis, Nathan J., Novitsky, Andrea L., Samson, Emil M., Thrift, William J., Ragan, Regina, & Guan, Zhibin. Large Continuous Mechanical Gradient Formation via Metal-Ligand Interactions. Germany. doi:10.1002/anie.201707587.
Neal, James A., Oldenhuis, Nathan J., Novitsky, Andrea L., Samson, Emil M., Thrift, William J., Ragan, Regina, and Guan, Zhibin. 2017. "Large Continuous Mechanical Gradient Formation via Metal-Ligand Interactions". Germany. doi:10.1002/anie.201707587.
@article{osti_1407836,
title = {Large Continuous Mechanical Gradient Formation via Metal-Ligand Interactions},
author = {Neal, James A. and Oldenhuis, Nathan J. and Novitsky, Andrea L. and Samson, Emil M. and Thrift, William J. and Ragan, Regina and Guan, Zhibin},
abstractNote = {},
doi = {10.1002/anie.201707587},
journal = {Angewandte Chemie (International Edition)},
number = 49,
volume = 56,
place = {Germany},
year = 2017,
month =
}

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on November 7, 2018
Publisher's Accepted Manuscript

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  • In this paper the authors examine critically the theory underlying discrete and continuous multiligand models for metal-humate binding. The concepts and equations that unify the various models are presented, and a general solution to the fundamental integral equation for ion binding in a multiligand system is given. Particular attention is paid to the continuous distribution models (normal distribution, affinity spectrum, and continuous stability function) which are relatively new tools in the field of metal-humate complexation. It is shown that the lower half and extreme right of the Gaussian ligand distribution assumed in the normal distribution model never affect metal speciationmore » measurably and hence are not knowable. It is also shown that an affinity spectrum does not correspond to an actual distribution of ligands; rather, each peak in the spectrum indicates the most probable stability constant controlling metal binding in a particular region of the experimental formation function. Application of the affinity spectrum model leads to a set of discrete ligands. A close examination of the continuous stability function model shows that it contains implicitly the same assumption as the affinity spectrum approach and thus leads also to discrete ligands.« less
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  • The electronic structures of a series of dinuclear uranium(V) complexes have been investigated using X{alpha}-SW molecular orbital calculations including quasirelativistic corrections. Complexes of the formula U{sub 2}H{sub 10} and U{sub 2}(OH){sub 10} were used to model the metal-ligand {sigma} and {pi} interactions, respectively, in the known species U{sub 2}(O-i-Pr){sub 10}. Two basic geometries were investigated: a vertex-sharing bioctahedron with only terminal ligands (D{sub 4h} symmetry) and an edge-sharing bioctahedron containing two bridging ligands (D{sub 2h} symmetry). The latter geometry, which is that of U{sub 2}(O-i-Pr){sub 10}, was also examined at U-U bonding and nonbonding distances. The calculations indicate that themore » U-U interactions are significantly perturbed when H is replaced by OH, owing to strong donation from the OH p{pi} orbitals into selected U 5f orbitals. The result is a lack of any appreciable U-U interaction for U{sub 2}(OH){sub 10} in either the D{sub 4h} or D{sub 2h} geometry. In addition, the overall OH {pi} donation to the U 5f levels is enhanced in the D{sub 2h} geometry. The electronic structure of a hypothetical U(V) dimer, Cp{sub 2}U{sub 2}O{sub 4}, was also examined in both bridged and unsupported geometries. The unbridged geometry, like that for U{sub 2}(OH){sub 10}, suffered from a destabilization of the U-U {sigma} orbital due to ligand {pi} donation and revealed no net U-U bonding. However, the geometry exhibiting two bridging oxo ligands maintains the U-U {sigma}-bonding MO as its lowest energy U 5f orbital. 21 refs., 8 figs., 8 tabs.« less
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