Is XeF4 violating the octet rule?

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Beryllium and boron are noted for frequently violating the octet rule, with beryllium forming compounds like BeF2 with four electrons and boron forming BF3 with six electrons. The superoxide radical (O2-) is discussed as a biradical with an unpaired electron, which does not violate the octet rule in its Lewis structure. The conversation also touches on sulfur's S8 ring structure, which does not violate the octet rule, and the stability of octet configurations due to quantum mechanical principles. Additionally, the discussion briefly mentions boranes, which typically do not satisfy the octet rule, and raises questions about the electron counting in compounds like XeF4. Overall, the thread explores the nuances of octet rule violations among second-period elements and related compounds.
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Is there any violation of the octet rule in the second period elements?
-scott
 
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Yes, beryllium typically bonds with 4 electrons (ie BeF2) and boron with 6 (BF3). Flourine is often involved in bonds that have more than 8 electrons (XeF4).
 
Also the superoxide radical, O2 with an extra electron. It's found in biological systems.
 
movies said:
Also the superoxide radical, O2 with an extra electron. It's found in biological systems.

Just to add, this is a biradical, with an unpaired electron on each oxygen atom.

~H
 
Hootenanny said:
Just to add, this is a biradical, with an unpaired electron on each oxygen atom.

~H

You mean singlet oxygen? That's different. In that case you haven't added an electron, in superoxide you have one more electron than you do in the regular oxygen molecule.

Anyway, I think that I was wrong. You can draw a Lewis structure for superoxide radical where you have 3 lone pairs on one O and two lone pairs plus one electron on the other, with a bond between the two. In that resonance structure it's not an octet rule violation. My mistake.
 
What about S8?
-scott
 
scott_alexsk said:
What about S8?
-scott

S is in the 3rd period...

Also, S8 is a ring of sulfur atoms, so there is no violation.
 
Why is octet configuration stable?
 
It just is.

Careful quantum calculations show that there is a deep local minimum of the potential energy for filled ns and np subshells. There are also shallow local minima at half-filled subshells. These are just the results of very complex calculations and it's hard to simplify things - in my opinion - to any considerable extent without being "a little" dishonest.
 
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  • #10
Nitrogen does interesting stuff as well - like in hydrazine
 
  • #11
Gokul43201 said:
It just is.

Careful quantum calculations show that there is a deep local minimum of the potential energy for filled ns and np subshells. There are also shallow local minima at half-filled subshells. These are just the results of very complex calculations and it's hard to simplify things - in my opinion - to any considerable extent without being "a little" dishonest.
thanks Gokul
I would request you to explain the difference between a wave and a particle? How would you describe the behaviour of an electron as a wave(qualitatively)?
 
  • #12
Malay, this question is fairly unrelated to the rest of this thread.

I have a couple of suggestions for you.

1. Read post #3 in the Physics FAQ thread : https://www.physicsforums.com/showthread.php?t=104715
It does not directly answer your question, but addresses some part of it.

2. If you still have something you want to ask, start a new thread in the appropriate Physics subforum - General Physics will work - and ask your question there.
 
  • #13
Gokul43201 said:
Malay, this question is fairly unrelated to the rest of this thread.

I have a couple of suggestions for you.

1. Read post #3 in the Physics FAQ thread : https://www.physicsforums.com/showthread.php?t=104715
It does not directly answer your question, but addresses some part of it.

2. If you still have something you want to ask, start a new thread in the appropriate Physics subforum - General Physics will work - and ask your question there.
Thanks for your help
 
  • #14
Why does oxygen not form o8, since it is in the same family as sulfur?Also what about the Boranes?
 
  • #15
One reason is the steric strain. Larger atoms like S, Se, Te can more easily accommodate non-ideal bond angles that are necessary to make the ring structures.

What about the boranes? Yes, they do not satisfy octets in general (see post#2, by cesium). Also look into Wade's rules for constructing boranes with n electron pairs.
 
  • #16
Does that mean that XeF4 follows the octet rule?
 
  • #17
try and draw out the structure of XeF4 and count the electrons. If you draw the correct structure your question should be answered.
 
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