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X-ray diffraction

X-ray diffraction. Laue’s and Bragg’s Treatments of X-ray diffraction. The path difference between the two rays reflected from successive planes is QA 2 + A 2 R = 2d sin θ

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X-ray diffraction

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  1. X-ray diffraction

  2. Laue’s and Bragg’s Treatments of X-ray diffraction The path difference between the two rays reflected from successive planes is QA2 + A2R = 2d sin θ Constructive interference is obtained if the path difference is equal to an intergral number of wavelengths (Bragg’s Law) 2d sin θ = nλ

  3. X-ray diffraction of N Phases

  4. X-ray diffraction of Sm Phases

  5. 2D WAXS Pattern of a Tetracatenar SmC Phase 120 ºC 0.7-0.75 nm

  6. Polymorphism of Discotic Mesophases uniaxial uniaxial biaxial Discotic nematic (ND) uniaxial Discotic hexagonal columnarColh or DhColho ordered;Colhddisordered biaxial Discotic rectangular and tetragonal columnarColr or Dr; Coltor Dt (Colh plastic crystal) Discotic oblique columnarColob or Dob

  7. Diffraction Pattern of a Hexagonal Columnar Mesophase with hk = kh = 10 is set to be 1 An additional peak can appear at 1.323 which was explained by a periodic electron density distortion (DeGennes, J. Phys. Letters, 1983 (44), L657).

  8. Diffraction Pattern of a Hexagonal Columnar Mesophase with hk = kh = 10 is set to be 1 An additional peak can appear at 1.323 which was explained by a periodic electron density distortion (DeGennes, J. Phys. Letters, 1983 (44), L657).

  9. Diffraction Pattern of a Pseudo-hexagonal Columnar Mesophase rectangular becomes pseudo-hexagonal if a = sq3 b So that b2 = a2/3

  10. 2D X-ray Diffraction Pattern of a Mechanically Aligned Sample of the ‘Chemical Mixture’ (M = Cu) sample Colh intercolumnar 21.0 Å X-ray beam intracolumnar 3.5 Å

  11. X-ray diffraction pattern of Cu52 at 90 ºC

  12. Temperature dependence of X-ray diffraction pattern

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