Visualizing the 30-Dimensional Antisymmetrized Electronic Structure of Water: The Emergence of Lone Pairs.

The electronic structure of water is typically thought of as exhibiting lone pairs of electrons, described by some as "rabbit ears". This is not the universal view, and it does not mesh with an interpretation based on the one-electron wave functions that emerge from molecular orbital theory. Here, we show, by analyzing the 30-dimensional antisymmetrized wave function (Slater determinant) rather than the Hartree product, that the water wave function indeed exhibits equivalent lone pairs. The observed photoelectron spectrum is reconciled with this view, in terms of a relaxation of this structure upon the loss of an electron. Therefore, the lone-pair viewpoint is shown to be completely consistent with both the experimental results and the calculated wave function.