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Published on: June 28, 2018
Multiple quadrupolar spin echoes in the La-filled skutterudite LaOs4As12
1Institute for Low Temperature and Structure Research, Polish Academy of Sciences, P.O. Box 1410, 50-950 Wrocław, Poland. B.Nowak@int.pan.wroc.pl
Solid State Nuclear Magnetic Resonance
|January 9, 2010
Summary
Researchers observed unique quadrupole echoes in lanthanum (La) Os4As12 using pulse nuclear magnetic resonance (NMR) studies. This finding provides a new method for assessing the structural symmetry and quality of LaOs4As12 samples.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nuclear Magnetic Resonance Spectroscopy
Background:
- Lanthanum Osmium Arsenide (LaOs4As12) is a material with potential applications in advanced technologies.
- Understanding the structural symmetry of crystalline materials is crucial for predicting and controlling their properties.
- Nuclear Magnetic Resonance (NMR) is a powerful technique for probing local atomic environments and symmetries.
Purpose of the Study:
- To investigate the structural symmetry of LaOs4As12 using 139La pulse NMR.
- To characterize the presence and behavior of quadrupolar echoes in LaOs4As12.
- To establish a new method for evaluating the quality and symmetry of LaOs4As12 samples.
Main Methods:
- Experimental measurements using 139La pulse NMR spectroscopy.
- Utilizing powder samples derived from high-quality single crystals of LaOs4As12.
- Observation and analysis of quadrupole echo patterns for 139La nuclei (spin I=7/2).
Main Results:
- Successfully obtained quadrupole echo patterns for 139La nuclei for the first time.
- Observed all predicted quadrupolar echoes for spin I=7/2 at specific time intervals.
- The presence of these echoes indicates a deviation from perfect cubic symmetry in the LaOs4As12 structure.
Conclusions:
- The observation of quadrupolar echoes serves as a direct indicator of deviations from perfect cubic symmetry in LaOs4As12.
- This NMR technique offers a simple and rapid method for assessing the quality and structural integrity of LaOs4As12 samples.
- The findings contribute to a deeper understanding of the physical properties and potential applications of LaOs4As12.
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