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Polarised neutron scattering from dynamic polarised nuclei 1972-2022
1Institut de Biologie Structurale, 38000, Grenoble, France. heinrich.stuhrmann@free.fr.
The European Physical Journal. E, Soft Matter
|June 6, 2023
Summary
Neutron scattering techniques, particularly using isotopic substitution and nuclear polarization, revolutionized contrast variation methods for studying materials. These advancements enabled detailed investigations of macromolecules and dynamic spin systems.
Area of Science:
- Condensed matter physics
- Materials science
- Biophysics
Background:
- The inauguration of the D11 small-angle neutron scattering instrument at the Institute Laue-Langevin (ILL) in 1972 marked a significant advancement in contrast variation techniques.
- Early adoption of isotopic substitution, particularly with hydrogen isotopes, rapidly led to high demand for the D11 instrument.
- Simultaneously, polarized neutron diffraction experiments demonstrated the utility of dynamic polarized protons in materials like lanthanum magnesium nitrate crystals.
Purpose of the Study:
- To highlight the revolution in contrast variation methods brought about by neutron scattering.
- To showcase the evolution and expansion of nuclear contrast variation techniques.
- To demonstrate the application of time-resolved polarized neutron scattering in studying dynamic spin systems.
Main Methods:
- Small-angle neutron scattering (SANS) with isotopic substitution.
- Polarized neutron diffraction and scattering.
- Nuclear polarization using novel target materials (frozen solutions).
- Nuclear Magnetic Resonance (NMR) and Electron Paramagnetic Resonance (EPR) techniques.
- Time-resolved polarized neutron scattering experiments.
Main Results:
- Neutron scattering, especially with isotopic substitution, revolutionized contrast variation.
- Nuclear polarization led to a boom in contrast variation for macromolecules using small-angle scattering.
- Polarized neutron scattering experiments from dynamic polarized protons were widely adopted in Europe and Japan.
- NMR and EPR expanded the scope of nuclear contrast variation.
- Time-resolved polarized neutron scattering successfully studied dynamic proton spins in free radicals and tyrosyl-doped catalase.
Conclusions:
- Neutron scattering techniques, enhanced by isotopic substitution and nuclear polarization, have profoundly advanced materials science and biophysics.
- The development of polarized targets and complementary techniques like NMR/EPR has broadened the application of contrast variation.
- Time-resolved polarized neutron scattering offers powerful insights into dynamic spin systems and molecular processes.
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