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I know of X-Ray diffraction, which produces a pattern corresponding to the inverse Fourier Transform of the lattice (reciprocal lattice). While this method is widely employed, it provides more information than I need - I don't want to find out what Bravais lattice I'm examining, but just how homogeneous this lattice is.

Which methods may be used to determine the homogeneity of the lattice? Can electron microscopes be used for this (SEM, TEM)? What spatial resolutions the additional methods posses?

EDIT:

I'm trying to figure out what techniques one can use in order to measure the lattice's deformation in vicinity of interfaces with another latices or amorphous materials (the picture is just a demonstration of such an interface between Si and Si02):

enter image description here

To my best knowledge, XRD does not provide high enough spatial resolution for this kind of measurements.

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SEM no.

With TEM you can see the atomic structure but only very local. It doesn't give you the idea of the whole sample. Besides, TEM is a much complex technique than XRD and involves a specimen preparation which may be very (very!) difficult and alter you sample.

Powder XRD is a simple technique, most of the times non destructive. You don't need to do a Fourier Transform... Powder XRD gives you a diffraction pattern with diffraction peaks. In a general way, sharper peaks means a more "crystalline" sample and well organized (closer to a single crystal). However this is not always straightforward (it depends on type of sample, material, size of particles...).

It would be helpful if you could say what type of sample are you trying to analyse.

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You are right in saying that I did not provide enough info. I'm trying to find alternatives to XRD because I need measure lattice deformation in isolated areas. XRD (to my best knowledge) does not provide the required spatial resolution. Edited the Q as well. –  Vasiliy Aug 6 '13 at 21:26
    
In that case, I'd say that High-Resolution TEM is your best option. –  cinico Aug 7 '13 at 8:50
    
I know that TEM can perform diffraction analysis as well. Assuming that circular area is analyzed, what is the minimal radius one would use, given that Silicon's lattice constant is $\sim 5.5 A$ (IOW, how many atoms are just enough to obtain a good diffraction data)? –  Vasiliy Aug 7 '13 at 14:47
    
If you use HR-TEM you probably won't need to acquire a diffraction pattern. Instead, you could look into the atoms and measure the distance directly. –  cinico Aug 7 '13 at 15:17

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