Thank you, very well explained! Appreciate this.
I assume though it follows the energy goes with the wave front, so that if would diffract once and then the photon interacts with the crystal a second time, it does not see the whole crystals, is this right?
When a photon interacts with matter and diffracts, the photon seems to interact with the area of its wave front, determined by an aperture even if it is only one photon. But how far does it interact in depth? Does it always "feel" the whole crystal? Can we assume the photon is reflected by the...