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first things first, I'm not by any means a physicist nor a student of physics. I study graphic design. Theme of my bachelor thesis is visualisation of physical and mathematical phenomenons, long story short I'm trying to create aesthetically pleasing depiction of electron.

Hopefully I made my homework, and got very rudimentary concept of orbitals all right. I also watched new Cosmos where in episode 5, electron of hydrogen is depicted, i tried to create similar depiction using Processing.

In Cosmos, Mr. Degrasse talks about "quantum leaps" where electron leaps from higher energy orbitals(and he exactly uses word orbital, not orbit) to the lower energy, and vice versa.

Cosmos depiction: (Sorry for gif's stutters, renderer problem probably)

cosmos

And here's my depiction: (leap, happens every 1.5 seconds, and always leaps from lower to higher, I haven't figured out other way yet. While Cosmos' electron's trajectory is depicted as flat surface, angle of mine changes with every leap. Due to aesthetics I omitted proportions of electron compared to nucleus)

orb

My questions are:

  1. Does electron have any kind of velocity, does it "move"? Or does it teleport "around" according to orbital probability function? And hence depiction in Cosmos is not correct?

  2. If it is not possible to pin down exact position of electron at given moment, is this way of depicting electron utterly wrong?

  3. Would large sphere filled with "points" that represent probability of electron's position depict electron's behaviour better? Considering we are working with Hydrogen's atom.

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  1. The electron does not move - it has no well-defined position in the orbital state, and hence no well-defined momentum. Neither does it "teleport" around - as long as it is not interacting with something that forces it to be at a definite position, its state is "smeared" all over the electron as an electron cloud.

  2. Yes, this is essentially the Bohr model, which is known to be false (and, since it is still taught in schools, the source for many a confusion about electron orbitals). Please do not perpetuate it.

  3. Why points? If you insist on visualizing it, the "smooth" pictures the Wikipedia page on atomic orbitals has are far better suited, for example:

enter image description here

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  • $\begingroup$ How does leap happen then? Does electron leap into every possible position? (as long as Orbital's probability allows "landing zone") Does electron exist in every possible position? Hence the smear? $\endgroup$ – Monocheddar Nov 25 '14 at 17:41
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    $\begingroup$ @Monocheddar: The electron has a probability to be found in every possible position. Until you look, it exists in neither of them, but only in a superposition of them - you cannot say where the electron is as long as it occupies the orbital state (and since the orbital states are those stable under time evolution, those are the states all electrons will be in in the real world), only where it can be found. One imagines it "smeared out" over the volume in which the probability to find it is non-neglegible. $\endgroup$ – ACuriousMind Nov 25 '14 at 17:50
  • $\begingroup$ "The electron does not move - it has no well-defined position in the orbital state, and hence no well-defined momentum." - Monocheddar should understand, though, that you can measure different variables for an electron, and that this statement is specifically meant to apply to precise energy measurements (each 'orbital state' has a well-defined energy). If instead you chose to periodically measure position and momentum to the most precise degree allowed by the uncertainty principle, you could see it "move" between successive measurements (not sure exactly what this would look like). $\endgroup$ – Hypnosifl Nov 25 '14 at 18:29
  • $\begingroup$ @ACuriousMind You are wrong, youtube.com/watch?v=Yii1u2Lz-II electrons do move, the have a well defined angular momentum. "it has no well-defined position in the orbital state, and hence no well-defined momentum" . Thats like saying: this car has no well defined position, therefor it doesnt move. photographymad.com/files/images/shutter-speed-motion-blur.jpg Do you even understand what you are saying bruv? $\endgroup$ – eromod Jan 1 '18 at 18:42
  • $\begingroup$ @eromod The phrasing in the answer is a bit off - it is not because it has no well-defined position that it has no well-defined momentum, but it is nevertheless true that the orbitals are stationary states with well-defined energy and angular momentum, but no well-defined position or linear momentum. In no meaningful sense of the word does an electron in an orbital "move". $\endgroup$ – ACuriousMind Jan 1 '18 at 20:00

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