1) can you scan rocking curve in a normal 2theta-theta diffractometer (Bragg brentano) bruker D5000?
2) which slides use?
3) what is the difference between FWMH obtained through a normal scan and the FWHM obtained by the rocking curves?
4)Can I have an idea of the extent of the defects of the material?
5) can you make the scanning on whole pieces of carbon-carbon materials?
6) it could be useful in the case of study of carbon-carbon materials?
can some one send me some papers?
Thanks in advance at all
Rocking curves you can always see if you are rocking something. The only question is how to interprete the results if you are rocking at simulatenously omega, theta, Phi and psi and... or only theta and omega (omega is usually called theta which is 1/2 2theta and describes the sample movement).
From my point of view, the meaning of rocking curves is to evaluate to intensity change of a single rocking axes. You can do the same with x, y and z although i wouldn't call it then "rocking" but the impact is the same: you are interested in the change of intensity in order to understand some "weired effect". The major question is, do you have unexpected investigations which gave you the intention to use rocking curves? Why do you want use rocking mode? Did you simply read something about this option or what do you expect? Easily explained, x and y I would use if I assume some kind of inhomogeneous size of grains, e.g. a single big grain which accidentally delivers an unexpected high intensity for a single hkl. Rocking curves can also help here, e.g. if a grain is only slightly misaligned and delivers a huge intensity slightly out of the diffraction plane defined by the primary and secondary beam. This can cause a shift in 2theta caused by the cone-shaped reflection ring and the secondary slit in front of the detector. Then you perhaps get a lot of intensity form this reflection at (sligtly) higher theta. In order to check this you simply rock your sample around one of the axis... Rocking 2Theta only makes sense if you assume a misalignment of the 2theta circle, or you don't exactly know 2theta for a specific phase and need to find the best position during measurement of a single crystalline material, etc. in orther words, there are several approaches to use rocking curves but you always need to know or have a very specific imagination what you are doing or what do you wnat see or what can happen. It is not always straight forward to interprete rocking curves.
From your question I would conclude that you don't know that much about rocking curves, the meaning and the capabilities and limits. You need to know, what do you do with rocking couves. If you understand this you can start to think whether this information can help you to solve one of your questions. Let's assume you have a deformed single crystal so that the size in reciprocal space does not describe anymore a spherical disk bit an elliptical disk. This gives some information about the applied glide planes and lattice rotations. These you can measure by rocking curves keeping 2theta constand and rocking about omega and psi or phi. What you will extract from the anisotropy of the intensity distribution is then not easy since it depends on the selected hkl, the material, the elastic constants etc. This is a huge problem, not easy to explain here and sometimes also speculative since there are good correlations for one material and not that good for others. It is not a technique as lattice parameter determination for powder XRD which also does not work properly for all materials. But on this area thousands of paople work so that several good and less good books exists. The problem of rocking is perhaps here and there considered but the problem is so specific that you can find something for multilayer material, technical single crystals like Ni-base superalloys, but an entire book about the rocking technique I do not know.
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