Mean square displacement evaluation by elastic neutron scattering self-distribution function
Salvatore Magazù1, Giacomo Maisano, Federica Migliardo
1Dipartimento di Fisica and CNISM, Università di Messina, PO Box 55, I-98166 Messina, Italy. smagazu@unime.it
Summary
This study presents a method for determining mean square displacement (MSD) using elastic incoherent neutron scattering (EINS) intensity profiles. The thermal behavior of MSD in PolyEthylene Glycol (PEG 400) was analyzed using this technique.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Neutron Scattering
Background:
- Mean square displacement (MSD) is crucial for understanding material dynamics.
- Elastic incoherent neutron scattering (EINS) provides insights into atomic motions.
Purpose of the Study:
- To develop an operational method for MSD determination from EINS data.
- To link EINS intensity profiles with the self-distribution function.
- To investigate the thermal behavior of MSD in PolyEthylene Glycol (PEG 400).
Main Methods:
- Utilized elastic incoherent neutron scattering (EINS) data.
- Employed the backscattering spectrometer IN13 at ILL, Grenoble.
- Analyzed data from a model system: PolyEthylene Glycol (PEG 400).
Main Results:
- Established a direct correlation between EINS intensity profiles and the self-distribution function.
- Successfully determined the total MSD and its partial contributions.
- Characterized the thermal behavior of MSD in PEG 400.
Conclusions:
- The presented method offers a reliable approach for MSD determination via EINS.
- The study provides valuable data on the dynamics of PEG 400.
- This work enhances the understanding of polymer dynamics through neutron scattering techniques.
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