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Hi I am doing an electron gun diffraction right now and I wonder why the angle below is 2 phi.
What I think about it that it's actually the results of two waves one is shown below and the other is a wave
with the same accident angle but negative "those two rays will be symmetric around the lattice plane" and all other rays will cancel each other. Thus will image in the screen is the result of the two rays and the angle between them will be 2phi.
Eventhough this makes sense to me, but I want to know is it true. and is there a proof that all the other rays"other than the twos" will cancel each other
What I think about it that it's actually the results of two waves one is shown below and the other is a wave
with the same accident angle but negative "those two rays will be symmetric around the lattice plane" and all other rays will cancel each other. Thus will image in the screen is the result of the two rays and the angle between them will be 2phi.
Eventhough this makes sense to me, but I want to know is it true. and is there a proof that all the other rays"other than the twos" will cancel each other
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