In my notes for a module on atomic and molecular physics it has this statement:(adsbygoogle = window.adsbygoogle || []).push({});

"For a given n the probability density of finding e- near the nucleus decreases as l increases, because the centrifugal barrier pushes the e- out. So the low-l orbitals are called penetrating."

I just want to clear a few things up to make sure I understand this correctly.

In a text book I found a good set of graphs comparing different combinations of n and l:

http://img.photobucket.com/albums/v319/Adwodon/IMG.jpg

Taking the n=3 set as the example, it appears to me that for l=0 the average distance is actually further from the nucleus than l=1,2.

However there are 2 other peaks which seem to be roughly the same distance as the most probable distance for n=1,2 (I don't know if this is just coincidental?)

So would I be totally wrong if I thought of these as sets of orbits (ie n=3 l=0 has 3 sets) and that low-l orbitals can 'penetrate' into sets of orbits which are closer to the nucleus (which are of a similar orbits to lower energy orbitals). As l increases the electron can no longer "penetrate" into lower sets due to increased angular momentum / centrifugal barrier(?), and the most probable position of the individual sets moves closer to the nucleus.

For example (distances are made up and represent the location of the peaks):

n=3 l=0 has

Set 1 @ r=1 , Set 2 @ r=5, Set 3 @ r= 15

at n=3 l=1, set one is now inaccessible and set 2 /3 have moved closer:

Set 2 @ r=4.5, Set 3 @ r= 14

and for n=3 l=2 both set 1/2 are inaccessible

Set 3 @ r=12

Although I cant say I really know why the average position would move closer to the nucleus as the angular momentum is increased?

Ultimately im just trying to put it into a form I can understand rather than have to learn by rote so unless my thinking is completely self defeating I don't mind if it doesn't give a totally accurate picture.

Also please correct me if i'm using incorrect terminology, this is all fairly new to me and ive always been slow when it comes to buzzwords.

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# Radial probability density / quantum numbers.

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