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Re: [Phys-l] Band splitting in Carbon (diamond)...



Short, intro answer - Pauli Exclusion Principle.

One hour lecture on the Kronig-Penney Model:

http://www.springerlink.com/content/g2882g5011j10154/fulltext.pdf

I have heard of folks writing a 'fairly simple' computer prg to show the wave func. as the atoms approach.


At 1:14 PM -0700 3/1/10, Jeff Loats wrote:
Greetings,

I am teaching a modern physics course and we are discussing the way in which
very similar valence electron configuration (2 electrons in a p-shell) leads
to very different conduction behaviors for carbon, silicon, germanium, etc.
My solid state is pretty rusty so I am seeking some help.

As we bring many C atoms together, the 2s and 2p bands mix together.
However, if you bring them even closer together a split occurs, creating the
valence and conduction bands for C, SI, etc.

I am having trouble finding a good sophomore-level description of what
causes the splitting to occur. That is, why don't the 2s and 2p bands just
continue to overlap, forming one huge band? What is the mechanism for the
later split.

Thanks for your help!

Jeff

--
Jeff Loats, Ph.D.
Assistant Professor of Physics
Metropolitan State College of Denver
Office: NC 3123F
Phone: 303-900-2175
Email: jloats1@mscd.edu or jeff.loats@gmail.com
Website: www.mscd.edu/physics/loats/

"Our imagination is stretched to the utmost, not, as in fiction, to imagine
things which are not really there, but just to comprehend those things which
are there." ~ Richard Feynman, The Character of Physical Law
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