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Overlapping orbitals of electrons


druS

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Guys, I'm having trouble with another really basic concept so I hope you can sort me out.

Let's just look at the spherical orbitals. In the usual diagrams the 1s orbital completely is inside the 2s orbital. But Pauli excludes this.

Is the 2s orbital actually a sphere with a (1s size) hole inside of it?

This overlap can be carried through to the 2p etc orbitals. In a massive atom that inner sanctum of 1s volume, against Pauli, could get very busy.

Cheers

 

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Pauli is safe.

 

:)

 

These two extracts should clear it up.

The plot of the radial distribution function in Fig9 of the first one shows quite clearly that the high density / high probability regions do not overlap.

Extract 2 presents an alternaive view of the same thing.

 

good luck.

 

s_orbitals1.jpg.3a822b6f74fbe80b8de1eb58ca92356f.jpg

 

 

s_orbitals2.thumb.jpg.86a6b64acb9c2657af83adbad73ca2a8.jpg

Edited by studiot
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13 minutes ago, swansont said:

Physical overlap isn't the restriction. Pauli means the states have to be different. Energy, spin, orbital angular momentum. Position is not a quantum state.

Good point, thanks. +1

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Thanks guys, as usual dropping questions here leads to interesting discussions I had not considered. Note that (at this stage) my studies are chemistry, not quantum - though without doubt this is starting with "sub atomics" and in particular the actions of the electron. [clearly moving toward chemical bonding.]

This said - swansont, if Pauli exclusion relates to energy and spin (can I leave out orbital angular momentum for now?), the the 1s and 2s orbitals (for example) can never be other than excluded as they are different energy levels to start with? This would cover the matter for all orbitals that appear to share space/volume.

In terms of "position is not a quantum state" my visualisation gets caught again - what happens when molecules - or make it simpler, two monoatomic elements meet. More specific, noble gases so we are not dealing with bonding complications. The electrons simply don't notice the orbital space of the other when they "rub shoulders"?

studiot

I must be reading those diagrammes incorrectly - Fig 9 seems to me to clearly show the 1s and 2s orbitals overlapped. Or that their is a probability of the 2s orbital with an electron positioned (that word again) in the 1s orbital probability.

 

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20 minutes ago, druS said:

 In terms of "position is not a quantum state" my visualisation gets caught again - what happens when molecules - or make it simpler, two monoatomic elements meet. More specific, noble gases so we are not dealing with bonding complications. The electrons simply don't notice the orbital space of the other when they "rub shoulders"?

They're still charged, and would tend to induce a dipole moment in the other atom, and have one induced in it.

20 minutes ago, druS said:

I must be reading those diagrammes incorrectly - Fig 9 seems to me to clearly show the 1s and 2s orbitals overlapped. Or that their is a probability of the 2s orbital with an electron positioned (that word again) in the 1s orbital probability.

Yes, the positions can overlap, but the energy is not the same.

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9 hours ago, swansont said:

They're still charged, and would tend to induce a dipole moment in the other atom, and have one induced in it.

Yes, the positions can overlap, but the energy is not the same.

 

Cheers Swansont

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On 3/11/2018 at 12:48 AM, swansont said:

Physical overlap isn't the restriction. Pauli means the states have to be different. Energy, spin, orbital angular momentum. Position is not a quantum state.

 

Guys, I thought I should revisit my thanks  here. You give a perspective that simply doesn't come from a uni subject on basic chemistry. Hey, you offered me a quantum physics "rabbit hole" to chase. And I appreciate it. In time, in time.

Right now an issue I had in Chemistry has evaporated.

Go to to say thanks, no honest really thanks, for that.

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To build upon what's been said, an electron is a negative charge in motion.  A charge in motion; negative or positive, will create a magnetic field. Each orbital has two electrons with opposite spin. This allows their magnetic fields to attract to compensate for the charge repulsion. Same spin electrons have magnetic and charge repulsion, and are not stable in a single orbital. 

When you start to stack S-orbitals, one variable that changes is the electrons of the inner S-orbitals will move faster than the electrons in the outer S-electrons. It is sort of like the skater pulling their arms in to spin faster. The affect is the inner electrons move faster and will generate a stronger magnetic field; to offset the close charge proximity. The result is a type of segregation based on minimizing energy. 

This segregation is not only connected to electron speed, but is also connected to wave addition. Opposite spin electrons generate magnetic fields that are 180 degree out of phase. These waves will cancel. The net affect is the electron orbital pair, minimizes its own EM energy,  while the cancelling of the magnetic wave addition, makes this invisible to the next orbital layer; hidden. If two stacked S-orbitals try to interact, EM energy is not minimized. 

Edited by puppypower
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1 hour ago, puppypower said:

To build upon what's been said, an electron is a negative charge in motion.  A charge in motion; negative or positive, will create a magnetic field. Each orbital has two electrons with opposite spin.

Each filled orbital. You can have unpaired electrons in different oribitals.

1 hour ago, puppypower said:

This allows their magnetic fields to attract to compensate for the charge repulsion. Same spin electrons have magnetic and charge repulsion, and are not stable in a single orbital. 

Not allowed in the same orbital, owing to Pauli.

1 hour ago, puppypower said:

When you start to stack S-orbitals, one variable that changes is the electrons of the inner S-orbitals will move faster than the electrons in the outer S-electrons. It is sort of like the skater pulling their arms in to spin faster. The affect is the inner electrons move faster and will generate a stronger magnetic field; to offset the close charge proximity. The result is a type of segregation based on minimizing energy. 

The angular momentum of an S orbital is zero — there is no contribution to magnetic moment from orbital effects. Spin effects only, and these will cancel if there are two electrons, as the spins will be anti-aligned.

There is no point of speaking of an electron's speed.

 

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