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DOE OSTI · 22436570

How far do electrons delocalize?

Scalmani, Giovanni·Frisch, Michael J.
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Abstract

Electron delocalization is central to chemical bonding, but it is also a fundamentally nonclassical and nonintuitive quantum mechanical phenomenon. Tools to quantify and visualize electron delocalization help to understand, teach, and predict chemical reactivity. We develop a new approach to quantify and visualize electron delocalization in real space. Our electron delocalization range function EDR(r{sup -vector};u) quantifies the degree to which electrons at point r{sup -vector} in a calculated wavefunction delocalize over length scale u. Its predictions are physically reasonable. For example, EDR(r{sup -vector};u=0.25 bohr) is close to one at points r{sup -vector} in the cores of first-row atoms, consistent with the localization of core electrons to ∼0.25 bohr. EDR(r{sup -vector};u=1 bohr) is close to one at points r{sup -vector} in typical covalent bonds, consistent with electrons delocalizing over the length of the bond. Our approach provides a rich representation of atomic shell structure; covalent and ionic bonding; the delocalization of excited states, defects, and solvated electrons; metallic and insulating systems; and bond stretching and strong correlation.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYATOMSCHEMICAL BONDSCORRELATIONSELECTRONIC STRUCTUREEXCITED STATESREACTIVITYSOLVATED ELECTRONS

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Scalmani, Giovanni, Frisch, Michael J.. 2014-10-14. How far do electrons delocalize?. https://doi.org/10.1063/1.4897264

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