About electrons at specific region around the atom ?

[fay's unKle]

I have a thing going on with the whereabouts of electrons in atoms and how they bond to form molecules, so when I read something surprising like this, I chase it hoping to get a little more insight into the subject. "Both single electrons now become paired and share the overlapping energy levels i.e. they can now also move in the energy level of the electron from the other atom so they can now move around each nuclei. However, most of the time they are found in the region between both nuclei as they are attracted by both nuclei."

They are talking for almost specific (?) electrons being at specific region around the atom. Where such findings are coming from. Are these theoretical or experimental findings. Pump-probe spectroscopy, photoelectron spectroscopy and crystallography, is all I only know to find electron energies and densities, but not positions as accurate to say that specific electrons "are found in the region between both nuclei"

Through which methods and what measurements they find that electrons are moving around both nuclei.

Would you know what to read to appreciate in its full extent the experimental procedures that lead to such findings/conclusions, other than the theoretical background of orbitals, valence octats etc.

[swansont]

It's the application of the same basic theory (QM) to molecules that predict the modification of the orbitals. Saying that the electron density increases between the nuclei is the same as saying the electrons are more likely to be found between them.

 

You can find a number of experiments that image the electron orbitals by searching on 'molecular orbital imaging' and similar terms

[Strange]

Well, apart from theory and indirect measurements, it is also possible to directly image electron density and see how this corresponds to theory, for example:

http://www.nature.com/nchem/journal/v3/n4/full/nchem.1008.html?wt.ec_id=nchem-201104

[Enthalpy]

While the general idea isn't too wrong, the sentence cited in the first post uses inaccurate wording.

 

Orbitals are stationary, so each and every word suggesting a movement is incorrect: "move", "most of the time" and so on.

 

Was the question about "specific" electron? Then the answer is a clear "no". There is now way, in theory nor in experiment, to distinguish electrons. But this abuse is very common because proper wording is impractical. For instance, we may say "electron capture involves a 1s electron" but it isn't strictly correct. Problem: the true solution is a single wave function for all electrons, so there are no distinct orbitals in an atom with 3 electrons or more, and then we could forget any kind of reasoning.

 

If the question was about electrons delocalized to both nuclei: yes. This is both modelled and observed.

 

And the trick about paired electrons is only that opposite spins permit them to share the same orbital. When two atoms get close, the atomic orbitals interfere to create a favourable molecular orbital and an unfavourable one. The electrons ability to be both in the favourable one permits bonds. This depends on the number of electrons and the number of favourable orbitals. For instance N₂ puts all electrons on bonding molecular orbitals so this bond is very strong and the molecule inert. O₂ has two electrons more which must go to antibonding molecular orbitals, so the bond is weaker and the molecule active. F₂ has again two electrons more, the bond is weak and the molecule reactive.