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big man

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**Question 1**— Construct the crystal lattice from the diffraction pattern drawn on page 5 of this exam paper making sure you include the (110) and (220) planes. Explain the procedure used in reconstructing the crystal lattice. What Bravais lattice is represented by the diffraction pattern

Image: http://img329.imageshack.us/img329/4036/reciprocal1bm8.jpg

**— I don’t know where to start on this one at all. I don’t know how the reciprocal lattice vectors will be defined and even if I did, I don’t know how to translate this to the crystal lattice (for this case). Yes I do know that the same equations apply as with the case below, but it's not clear since I had some conflicting information from this site here:**

__Problem__http://www.chembio.uoguelph.ca/educmat/CHM729/recip/6reci.htm

Alos, is this pattern of a rhombohedral structure?

**Question 2**— Construct the crystal lattice from the diffraction pattern drawn on page 5 of this exam paper making sure you include the (440) and (220) planes. Explain the procedure used in reconstructing the crystal lattice.

Image: http://img141.imageshack.us/img141/4531/reciprocal2lk5.jpg

**— With this question I know how to define the reciprocal lattice vectors and from the equations I can see that the crystal lattice vectors are in the same direction. The only thing I’m not sure about is the meaning behind the fact that there are no in-between planes (the set of planes with indices of 1 and 3). This construction of the crystal lattice was a stab-in-the-dark attempt and I don't know the why behind it (I really want to know how and why I'm doing something).**

__Problem__If someone could please take a look at these questions I'd really appreciate since I can't find any information on these types of problems on the internet. Our notes also don't cover it because the lecturer believes that we should be able to research things properly...

Thanks

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