1s orbital overlaps with the nucleus, why don't they interact?

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Granted, the size difference between a hydrogen atom's electron cloud and its nucleus is a factor of one million (~1Å vs ~10^-6Å), but that's still a significant amount of overlap that, I would think, would trigger the occasional interaction.

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blue_leaf77
Homework Helper
They do interact, in most considerations indeed the nucleus is treated merely as a point and hence dimensionless charge. But if more accurate energy levels are desired, various corrections, usually treated as perturbations, must be incorporated into the Schroedinger equation. The one that pertains the finite size of the nucleus is the volume effect.

phyzguy
Indeed they do. Electron capture is a type of radioactive decay where the nucleus absorbs an inner shell electron. This doesn't happen in hydrogen because it isn't energetically favorable; the resulting neutron has more mass than the hydrogen atom.

Radioactive isotopes that decay by pure electron capture can be inhibited from radioactive decay if they are fully ionized ("stripped" is sometimes used to describe such ions). It is hypothesized that such elements, if formed by the r-process in exploding supernovae, are ejected fully ionized and so do not undergo radioactive decay as long as they do not encounter electrons in outer space.
That. Is. So. Cool.

Staff Emeritus
2019 Award
But if more accurate energy levels are desired
To expand on this, the effect also changes the number of energy levels for the hydrogen atom, not just their value. There is the well-known k-l degeneracy, where the n=2 l=0 level has the same energy as the n=2 l=1 level. But because the l = 0 level spends more time "inside" the nucleus, it has a larger energy shift than the l=1 state, breaking the degeneracy.

davenn
Gold Member
2019 Award
Indeed they do. Electron capture is a type of radioactive decay where the nucleus absorbs an inner shell electron.
cool, learn something new every day :)

As I recall, part of it talks about how the electron wave function overlaps the proton wave function differently than the muon does in muonic hydrogen. It is offered up as a possible explanation of why the proton radius appears to be different when muons are substituted for electrons in one method for measuring the the proton radius.

You probably mean react , not interact.
The hydrogen atom is produced by electron-proton interaction.

I would think the previous discussion in this thread indicates that I was indeed talking about interaction between the electron's wave function and the proton's, not just a chemistry consideration. I was wondering why, if the the highest probability of an 1s electron is smack in the middle of the nucleus, why there aren't obvious interactions between the two. As was indicated in the replies here, there are indeed interactions resulting from that.

blue_leaf77
Homework Helper
the the highest probability of an 1s electron is smack in the middle of the nucleus
It seems like you forget that the radial probability of a hydrogen-like atom is given by $r^2|\psi_{nl}(r)|^2$, the presence of $r^2$ makes the probability inevitably zero in the origin and the maximum is shifted to a further distance.

Mister T