[Mazin]

I am studying Chemistry at a HE Access course which is A Level standard chemistry.

We have covered Atomic Structure and I am now revising for an end of term test.

On reviewing the S, P, Do orbitals etc I have become confused about the Orbitals and the Pauli Exclusion Principle which states that no two electrons can have the same 4 quantum numbers. 

I understand the orbital is thought of as a volume of space where there is a high probability of finding an electron. But as you progress up to higher orbitals, aren't you going to get a situation where there is an overlap of orbitals?  For example the 3s spherical orbital will surround the 1s, 2s, and 2 p orbitals in part.  Does this violate the Pauli exclusion principle in that the 1s, 2s and 2p orbitals are in the same space as the 3s orbital? 

Can you explain what's wrong with my thinking?  Thanks

[Irlanur]

I am afraid you won't get around some math to understand this better. Did you hear about the Schrödinger equation and wavefunctions? and what orbitals really are?

why do you think that the overlap (as you define it) is a problem?

just saying: Orbital overlap is a mathematically well-defined quantity and the meaning is a bit different than yours...

[Mazin]

I am afraid you won't get around some math to understand this better. Did you hear about the Schrödinger equation and wavefunctions? and what orbitals really are?

why do you think that the overlap (as you define it) is a problem?

just saying: Orbital overlap is a mathematically well-defined quantity and the meaning is a bit different than yours...

Thanks for replying

I have heard about the Schrodinger equation and I know that that is where 3 of the 4 quantum numbers came from.  I haven't studied it yet.

You asked me is it a problem if orbitals overlap?  I suppose not.  I was thinking that if the spatial co-ordinates were identical then they would have the same quantum numbers, but thinking about it a bit more I don't think that's the case.  Do the electron density maps show max density where there's maximum overlap of orbitals?  I believe they show max density near the nucleus, but in a "big" atom, with d and f orbitals, wouldn't you be able to see higher density where these orbitals overlap away from the nucleus? 

With the electrons carrying a charge, I am certain that they can't be in the same space at the same time. 

I know that you can't know the location and momentum of an electron, but I my studies so far the s,p,d orbitals have been discussed separately, but when I think of the atom as a whole I visualise that these orbitals occupy much the same space and nothing has been said about that

[Mazin]

When do you study the Schrodinger equation at University?  Is it easy for an undergraduate to understand?  I know it is a key piece of science, but that doesn't necessarily mean that it is difficult?

Should I be scared?  Will it fry my brain?  I haven't done calculus yet.  I don't think it's a good idea for me to research this because I could get distracted and perhaps disheartened if I don't understand it.  I suppose it's taught at a certain time when you have the right level of base knowledge

What annoys me a little with science is that you learn something at one level, and then you find a couple of years later that actually that wasn't true, and its like this. eg Bohr model is wrong.  Well why didn't you just tell us the proper science first.....it doesn't necessarily have to be complicated.

You can learn orbitals and sub shells without knowing the maths.  What weve been taught in our HE Access course isn't complicated.  No more complicated than the Bohr Model and Pudding models.  Just different

[Irlanur]

What annoys me a little with science is that you learn something at one level, and then you find a couple of years later that actually that wasn't true, and its like this. eg Bohr model is wrong.  Well why didn't you just tell us the proper science first.....it doesn't necessarily have to be complicated.

Let's put it like that. Most chemists are molecule engineers, a feeling for the building blocks and there junctions is more important than a fundamental understanding. An organic chemist in the industry will probably solve equations very rarely. Most models taught to chemists are working models rather than fundamental understanding. Sometimes details also hide what we can learn. The best assumption during undergraduate studies is thus probably that nothing you learn is actually completely true.

Coming back to the Schrödinger equation: It's often said that this is the fundamental equation of atoms and chemistry. In fact, it's not, because it does not include relativity and e.g. spin has to be introduced ad hoc. I'm afraid it's really complicated because I always found that true understanding includes the mathematics as well as knowledge of the chemical and physical consequences. You certainly don't have to be afraid, just accept that it takes more time and effort. your teacher definitely does not except you to know a lot of it. I would guess he probably does not know too much about it.

You can learn orbitals and sub shells without knowing the maths.  What weve been taught in our HE Access course isn't complicated.

It's probably also wrong in many points.

PS: yes I am a pain in the ass and nit-picker when it comes to orbitals
 

[Borek]

Technically every possible orbital occupies all the space from the nucleus to the infinity.