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This Question may seem simple at first sight, however I've been thinking quite a bit about it lately and can't get to a solution.

This is where I'm at:

An Atom is made up of Protons, Neutrons and Electrones. The Nucleus consists of Protons and Neutrons. The Electrones are distributed on the shells and move freely on that shell.

Due to the fact, that they(Electrons) have the same charge, they repel each other.

Am I right so far, or am I missing the point?

Anyway, here's what I'm thinking:

The Electrons have to have the same distance to all the other electrons, because otherwise, one would be slowed down by the magnetic field of the one in front of it.

If an electrone is slowed down, it gets closer to the core of the atom.

This works perfectly fine on the first shell, there are 2 Electrons, which are then always on the opposit side of one another.

However if you'd go on the next shell, things become more interessting: Now there are 6 Electrones. The only way to distribute the Electrons evenly on the Atom, so that all can move with the same speed and the same distance to eachother, is to put them all in the same orbit moving at the same speed in the same direction. This brings the problem that all electrones are relatively close to eachother and a large parts of the Atom is not "orbited" by electrones, also, they would probably reject each other.

In this case there is the following problem: when all Atoms are evenly distributed around the core (imagine like satelites around the earth) with everyone having the same distance to it's neighbours. you encounter a new problem. - You can't move the electrones in any directions without:

  1. Changeing the distance between the electrones (bringing them closer together and therefore having them to push eachother of their orbit)
  2. Keeping the distance but having a weired orbit (for example if earth were the nucleus) having one going around the equator and having one only hovering over the northpole) that one would have to withstand the magnetic pull, but with noforce pulling it out.
  3. they are constantly changing shells and pushing eachother around (however this would lead to slowing eachother down until the atom collapses) also there would currentl't be a chance to assign a number of electrons to a particular shell. And a very instable Atom.

I can't explain (to me) how they can symontaniously be evenly distributed and moving at the same speed? How is this possible?

How can an Atom be stable and not collapsing?

Somehow I cant understand, how the electrones are on the atom distributed.

I'm not looking for a lecture about how the atom is built and infos about the shell-system, but rather how the distribution of the Electrons around the Atom in motion look like. I would have added images to further explain my point, but I'm new and can't do so yet.

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  • $\begingroup$ 1) You won't be able to understand what shells are without quantum mechanics. 2) the interesting problem of the distribution of electrons on a sphere that minimizes the potential energy is called the Thomson problem: en.wikipedia.org/wiki/Thomson_problem. Note that this won't tell you anything (or very little) about the structure of atoms. $\endgroup$ – doetoe Dec 23 '16 at 15:14
  • $\begingroup$ @doetoe Yes, you're right, I probably won't be able to fully understand what shells are. The Thomson problem discribes pretty much what I tried to discribe as a part of my question. Thank you. I'd give you an upvote, but I can't vote yet. $\endgroup$ – Frezzley Dec 23 '16 at 15:22
  • $\begingroup$ doetoe's comment should be copied into the answer box, i think. $\endgroup$ – JMLCarter Dec 23 '16 at 16:10
  • $\begingroup$ Have you looked into electron orbital configurations? There are graphical representations that may be able to speak worlds into your inquiry. Also, I want to add that if you wamt to delve deeper into particle physics, you have to relinquish the idea that particles are little round balls because they actually aren't (yet they are). You will need to understand their wave functions and treat them like so as it will make so much more sense later on. $\endgroup$ – Rincewind Dec 24 '16 at 18:35
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The electrons in an atom do not have a position. They are delocalised over the whole atom. So the question of how the positions of the electrons are arranged is meaningless.

In the macroscopic world we take it for granted that an object, e.g. a tennis ball, has a well defined position. However when we get down to the size range where quantum effects become important we find that quantum objects like electrons are described by wavefunctions that are spread out over some region of space. In particular the electrons in atoms are not like little balls but are more like fuzzy clouds, and these fuzzy clouds all overlap with each other.

We can get an approximate description of the electron distribution in atoms by using the self consistent field approximation, and this gives us the well known $s$, $p$, $d$, $f$, etc atomic orbitals:

Atomic orbitals

The total electron density is then obtained by summing up the orbitals that are populated by electrons. As it happens I did a final year project on calculating the electron densities in atoms and it is surprisingly boring. In the absence of any external perturbation the electron density is spherically symmetric and falls off in a roughly exponential fashion with distance from the nucleus.

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  • $\begingroup$ John, I'm obsessed by the idea that the magnetic dipole moments of the involved electrons are the reason for the shells with 2, 8 and 8 electrons. The symmetrical distribution is perfect. 4 electrons with spin up and 4 with spin down are in perfect equilibration. Imagine two tetrahedra which form a octahedral structure. On the edges of the first tetraeder are the spin up electrons, on the other tetraeder are sitting the spin down electrons. Tell me which phenomenons in nature are not consistent with such an explanation. Not tell me what was interpreted nearly 100 years ago. $\endgroup$ – HolgerFiedler Dec 23 '16 at 22:30

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