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Need help with xrd T_T

  1. Nov 18, 2008 #1
    Im Jessica , I got an xrd pattern that i cant figure it out. Can you guys help me to find out what it is :!!):shy::cry: or can anyone give me some idea what kind of material this is.(Apart from it's an amorphous.)

    Attached Files:

    Last edited: Nov 18, 2008
  2. jcsd
  3. Nov 18, 2008 #2
    this file is not a virus , Its just only an xrd
  4. Nov 18, 2008 #3
    There is no way to identify the material just from the angular distribution. The angle depends on what wavelength was used. The first step should be to calculate the d-spacing for the angles on the x-axis. Then you may try to see if these weak "peaks" may be associated with some known material. I don't think you have too much chance, there are very few features.
    Just some amorphous or glassy material.
    You need some chemical analysis (or x-ray fluorescence).
  5. Nov 22, 2008 #4
    Questions to ask yourself when sorting out XRD spectra:

    1) What crystal is it? BCC, FCC, HCP. Each type of crystal will have a series of forbidden reflections which can aid you in naming peaks in the spectra.

    2) Do you know roughly what the crystallinity of the sample is? Is it one you have grown via MBE, for instance? Has it been grown via a bulk growth method?

    3) Is your material a multilayer system? For instance a thin film on top of a tranisition metal or semiconductor like GaAs? If yes, you'll get peaks in the data from both sets of materials. This can help you identify the crystallographic orientation of the thin film relative to the substrate if it is an entirely new multilayer structure

    It is almost impossible to be given a spectra and simply say "this is material [x] with [y] lattice spacing". You need to have some idea of what you've got so you have a starting point. Moreover, using a simple rocking curve (intensity vs 2-theta) is only of limited use. If you have a material you think is of decent quality with good crystallinity extended over large distances then you should take reciprocal space maps to try and quantify how crystalline the sample is and see if you have twinning or other phases in your sample.
  6. Nov 26, 2008 #5
    You can do XPS to find the element percentage and state.
  7. Nov 27, 2008 #6
    Yes, in principle you can do both of those things, but you have to be careful. Analysing XPS data properly is more complicated than it seems it should be and unfortunately there are papers out there in the literature that have got it wrong.
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