2014 Fiscal Year Final Research Report
Correlation effects among thermal displacements of atoms by diffuse neutron scattering measurements
| Project/Area Number |
24510117
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Multi-year Fund |
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| Section | 一般 |
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| Research Field |
Quantum beam science
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| Research Institution | Ibaraki University |
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Principal Investigator |
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| Project Period (FY) |
2012-04-01 – 2015-03-31
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| Keywords | 散漫散乱 / 原子熱振動 / 中性子散乱 / フォノン分散関係 |
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| Outline of Final Research Achievements |
Neutron diffraction measurement of powder alpha-Fe sample was carried out at the high resolution powder diffractometer iMATERIA. The correlation effects among thermal displacements of atoms were estimated. The force constants among atoms were obtained using an equation for transforming of the correlation effects to force constants. The force constants and the crystal structure of Fe were used to estimate the phonon dispersion relations, phonon density of states, and specific heat by computer simulation. Neutron diffraction measurements were performed on powder Cu2O with different samples that are pressure released after a pressing force. Peak widths of Bragg lines increased depending on the pressing force. To clarify the relation between the crystallite size and the microstrain effect, Rietveld refinenement analysis was performed. The increasing peak width according to the dependence of pressing force is mainly derived from strain effects.
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| Free Research Field |
X線中性子回折
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