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Are covalent bonds really directed?

  • I. David Brown EMAIL logo
Published/Copyright: March 4, 2016
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American Mineralogist
From the journal American Mineralogist Volume 101 Issue 3

Abstract

The flux theory of the chemical bond, which provides a physical description of chemical structure based on classical electrostatic theory, correctly predicts the angles between bonds, to the extent that they depend on the intrinsic properties of the bonded atoms. It is based on the justifiable assumption that the charge density around the nucleus of an atom retains most of its spherical symmetry even when bonded. A knowledge of these intrinsic bond angles permits the measurement and analysis of the steric angular strains that result from the mapping of the bond network into three-dimensional space. The work ends by pointing out that there are better ways of characterizing bonds than describing them as covalent or ionic.

Keywords: Bond angles; flux bonding theory; directed bonds; Invited Centennial article

Acknowledgments

I thank Barry Bickmore for stimulating discussions of the problems discussed in this paper and Matthew Wander for helpful comments on this manuscript.

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  1. Manuscript handled by Aaron Celestian

Received: 2015-1-8
Accepted: 2015-5-3
Published Online: 2016-3-4
Published in Print: 2016-3-4

© 2016 by Walter de Gruyter Berlin/Boston

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https://doi.org/10.2138/am-2016-5299
Keywords for this article
Bond angles; flux bonding theory; directed bonds; Invited Centennial article

Articles in the same Issue

  1. Editorial
  2. The most-cited journal in mineralogy and petrology (and what scientists can learn from baseball)
  3. Fluids in the Crust
  4. Fluids in the crust during regional metamorphism: Forty years in the Waterville limestone
  5. Research Article
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  7. Research Article
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  9. Dana Medal Paper
  10. Constraints on the early delivery and fractionation of Earth’s major volatiles from C/H, C/N, and C/S ratios
  11. Crossroads in Earth and Planetary Materials
  12. Octahedral chemistry of 2:1 clay minerals and hydroxyl band position in the near-infrared: Application to Mars
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  15. Spinels Renaissance: The Past, Present, and Future of those Ubiquitous Minerals and Materials
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  17. Spinels Renaissance: The Past, Present, and Future of those Ubiquitous Minerals and Materials
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  22. Compositional variation of apatite from rift-related alkaline igneous rocks of the Gardar Province, South Greenland
  23. Special Collection: Perspectives on Origins and Evolution of Crustal Magmas
  24. Dynamics and thermodynamics of magma mixing: Insights from a simple exploratory model
  25. Special Collection: From Magmas to Ore Deposits
  26. Geochemistry, petrologic evolution, and ore deposits of the Miocene Bodie Hills Volcanic Field, California and Nevada
  27. Research Article
  28. Recognizing sulfate and phosphate complexes chemisorbed onto nanophase weathering products on Mars using in-situ and remote observations
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