Why Do Electrons "Jump" in Orbitals?

[Dual Op Amp]

Alright, I have a question regarding quantum physics, but I don't want to post in that forum, because it scares me. I saw a website, it had an atom fill up electrons in orbital, as it got high, a rather unusual thing happened, an electron from an S orbital jumped to fill a P sub-orbital. I was wondering why this happens.

 

[santoshroy]

If the atom were to be the only one in the universe this would not have happened. Simply the s-electron would not jump to a sub p orbital. But an atom is contantly puturbed means constantly there is a "push" here and there.
So the atom wants to go to the state in which it is stable. So the phenomenon occurs.

 

[ZapperZ]

Alright, I have a question regarding quantum physics, but I don't want to post in that forum, because it scares me. I saw a website, it had an atom fill up electrons in orbital, as it got high, a rather unusual thing happened, an electron from an S orbital jumped to fill a P sub-orbital. I was wondering why this happens.

Your description is vague. Was this transition (from S to P) occurring WITHIN the same principle quantum level n?

If we are talking about the regular transition that occurs between different n levels, then the transition from "an S orbital to a P orbital" via the emission of a photon is due to a selection rule, or more precisely, the dipole selection rule. Describing it in words, there are two broad "rules" for such a transition:

(i) it must be between different n levels (example: the Balmer series)
(ii) it must be between orbital levels that is different by 1 angular momentum quantum number (i.e. s to p, p to s, p to d, etc... but NOT s to d)

This selection rule comes out naturally if you work out the dipole matrix element using the atomic wavefunction as the basis functions, i.e. it wasn't just made up out of thin air. It also a result of conservation laws, since the emission of a photon "creates" a particle with angular momentum of 1. Thus, the atom making that transition must also undergo a change in its angular momentum to preserve this conservation law.

Zz.

 

[Dual Op Amp]

No, that's not what I'm talking about Zapperz, this is.
http://lectureonline.cl.msu.edu/~mmp/period/electron.htm
This is a website that shows how electrons would configure in an atom.
I'm correcting myself, not a P orbital, but a D orbital. The electron jumps from a filled S orbital to a D orbital. I wanted to know why.

 

[ZapperZ]

No, that's not what I'm talking about Zapperz, this is.
http://lectureonline.cl.msu.edu/~mmp/period/electron.htm
This is a website that shows how electrons would configure in an atom.
I'm correcting myself, not a P orbital, but a D orbital. The electron jumps from a filled S orbital to a D orbital. I wanted to know why.

Next time, it helps if you show the site where you're reading all these things. Both santoshroy and I interpreted what you wrote as being an atomic transition! The LAST thing you want to do is annoy the people who put in the effort and time trying to answer your question. And I do get annoyed for spending time for nothing in responding to this.

The filling of the 4d orbital ahead of the 3d is primarily due to the closeness of the average position of the 4d electron when compared to the 3d orbital. This gives a lower energy state for the 4d. There are other more complicated answers for this which I no longer have the patience to go through.

Zz.

 

[Dual Op Amp]

Well, your schedule can't be that tight, considering you responded to my post in less than an hour. Anyone else?

 

[ZapperZ]

Well, your schedule can't be that tight, considering you responded to my post in less than an hour. Anyone else?

You're welcome. It's nice to know our efforts are so "appreciated".

Zz.

 

[Dual Op Amp]

Hey, you're the one who got impatient over two posts. You're efforts are "appreciated", but you don't want to ellaborate, so I'll look for a more descriptive reply.

 

[Dual Op Amp]

I think I might get it, the 4s orbital has a lower energy state than the 3d orbital. It fills first, but, as the 3d orbital is filling, it steals an electron from the 4s - wait a minute, it steals it to get to 5, that doesn't make sense.
Now I'm confused.
Edit - Ahah, now I got it. After doing a google search, I found out that more unpaired spins means a lower overall energy. That's why it jumps, but wait a minute how can more unpaired spins mean a lower overall energy?
http://antoine.frostburg.edu/chem/senese/101/electrons/faq/4s-3d.shtml

 

[Dual Op Amp]

Anyone have an answer?

 

[zefram_c]

When electrons get paired up, they are put in very similar spatial wavefunctions, which results in increased repulsion since they are both negatively charged. Different spatial wavefunctions are generally orthogonal, or in any event the overlap is much smaller. So if you are working with a number of states of approximately equal energy and fill them up with electrons, the electrons will first go to a completely empty state and only then go to states that are half-filled. I believe this is called Hund's rule.

Building up atoms by filling the p orbitals is a prime example. See http://www.webelements.com/webelements/properties/text/image-period-2sp/ionization-energy-1.html : note the ionization energy generally increases since the nucleus becomes more positive and the electrons with the same n do not shield each other. However, watch the decrease from nitrogen to oxygen: this is b/c in nitrogen the p orbitals are each half full, whereas oxygen's extra electron goes into another p orbital and the resulting repulsion actually wins out over the nuclear charge increase.

 

[Gokul43201]

Edit - Ahah, now I got it. After doing a google search, I found out that more unpaired spins means a lower overall energy. That's why it jumps, but wait a minute how can more unpaired spins mean a lower overall energy?

See Hund's Rule. Pairing electrons increases electron-electron interaction.

 

[t!m]

Long story short, orbitals are most stable when full, and second most stable when half-full. Some atoms will sacrifice a full Xs2 orbital and take away one electron, leaving a half-full Xs1 orbital. This electron will either be used to make an Xd4 into an Xd5 (now half-full and thus more stable), or an Xd9 into an Xd10 (now completely full and thus most stable).

 

[Dual Op Amp]

Alright, thank you. Why are orbitals more stable when full or half full?