hazem95

أ. د/ حازم محمود المشنب

استاذ - عميد كلية العلوم بسوهاج

كلية العلوم

العنوان: جامعة سوهاج - كلية العلوم - قسم الفيزياء

23

إعجاب

Mössbauer Spectroscopy

2018-09-24 05:46:10 |
  •  Mössbauer spectroscopy

    Mössbauer spectrometry is based on the quantum-mechanical “Mössbauer effect,” which provides a link between nuclear and solid-state physics.

    In Mössbauer spectrometry one nucleus emits a γ ray and a second nucleus absorbs it.

    • It can give very important information about:
    • Chemical properties
    • Physical properties
    • Hyperfine Structure

    Most applications of Mössbauer spectrometry in materials science utilize “hyperfine interactions,” in which the electrons around a nucleus perturb the energies of nuclear states.

    Hyperfine interactions cause very small perturbations of 10–9 to 10–7 eV in the energies of Mössbauer γ rays. For comparison, the γ rays themselves have energies of 104 to 105 eV.

    These small hyperfine perturbations of γ-ray energies can be measured easily, and with high accuracy, using a low-cost Mössbauer spectrometer.

    Interpretations of Mössbauer spectra have few parallels with other methods of materials characterization. Perhaps NMR spectrometry is the best analogy, although the excitation energies are very different.

    A Mössbauer spectrum looks at a material from the “inside out,” where “inside” means the Mössbauer nucleus.

    The method is often useful because nuclear energy levels are altered by interactions between the nucleus and its nearby electrons.

    Mössbauer spectroscopy can be used in many areas of science such as:

    • Physics and Chemistry,
    • Used to further examine the nature of energy states in nuclei
    • Measure changes in chemical environment of nuclei
    • Monitor materials during phase changes
    • Monitor chemical reactions
    • Determine structures of molecules
    • Mineralogy and Metallurgy,
    • Can be used to determine metal samples
    • Determine crystal structures
    • Molecular arrangements
    • Chemical compositions
    • Used to analyze different mineral samples
    • Determine different crystal structures
    • Determine compositions
    • Biology
    • Used In Cancer treatments
    • Used to analyze red blood cells
    • Test environmental effects of human body
    • Can analyze protein structures
    • Help in function determinations
    • Used in combination with other data to obtain chemical information about proteins.
  • in this course we will study the following items
  • Nuclear magnetic resonance (NMR)
  • Nuclear quadruple resonance (NQR)
  • Mössbauer spectroscopy
  • Hyperfine Structure
  • Nuclear resonance
  • Recoil energy
  • Doppler effect 
  • Mössbauer Effect
  • Mossbauer spectrum and parameters
  • Mössbauer spectrum
  • Mossbauer factor
  • Isomeric shift 
  • Quadrupole splitting
  • Magnetic or hyperfine splitting, also known as the Zeeman effect.
  • Mossbauer Spectrometer
  • Applications
  •  

2018-09-24 10:10:05 Mössbauer Spectroscopy
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