(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

This question refers to Kittel's solid-state physics book.

I just do not understand the 1D example on pages 164-65. So, I understand everything until the line "The wavefunctions at [itex]k = \pm \pi/a[/itex] are not the traveling waves [itex]\exp(i\pi x/a)[/itex] or [itex]\exp(i\pi x/a)[/itex] of free electrons."

Kittel tries to explain, but I just don't understand. Is he saying that they will just bounce back and forth between k = pi/a and k = -pi/a by Bragg reflection? How does he know that!?!?!? PLEASE HELP!!

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Kittel nearly free electron model

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