Crystallography, reciprocal lattice & diffraction. Lecture 6 of 9

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  • Опубліковано 2 гру 2024

КОМЕНТАРІ • 4

  • @purnimakumari4832
    @purnimakumari4832 3 роки тому

    Hello sir, Thanks a lot for nice explanation. Do you have videos or study materials about design of del trip steel of high aluminum.

    • @bhadeshia123
      @bhadeshia123  3 роки тому +1

      Have a look at the following to see whether there is anything suitable:
      www.phase-trans.msm.cam.ac.uk/pubs/pt.html

  • @hikguru
    @hikguru 4 роки тому

    Hello Dr. Bhadeshia. Thanks for explaining such an abstract concept so clearly. The 1/lambda (Ewald sphere radius) for electrons is much higher than for X rays. Does that mean that the sphere in electron diffraction intersects more reciprocal lattice points and thereby we can get more reflection spots? So if true then for a given film thickness the XRD would not give as many reflection spots as electron diffraction?
    Also if the film is polycrystalline then even if it is thick can we expect several diffraction spots (more than single crystalline), since each grain of this film would give a different arrangement of reciprocal lattice points?

    • @bhadeshia123
      @bhadeshia123  4 роки тому

      When looking at a thin foil in a transmission electron microscope, the weighted reciprocal lattice points can be considered to be extended as spikes normal to the plane of the foil. Therefore, an Ewald sphere with a larger diameter in reciprocal space will intersect more of those points. Yes, with a polycrystalline sample, rings of diffraction spots.