2016 Fiscal Year Final Research Report
Construction of Structure Models of Iron Hydroxide Nanominerals Using Scanning Transmission Electron Microscopy (STEM)
| Project/Area Number |
26400512
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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 |
Petrology/Mineralogy/Economic geology
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| Research Institution | Niigata University |
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Principal Investigator |
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| Project Period (FY) |
2014-04-01 – 2017-03-31
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| Keywords | STEM / ferrihydrite / schwertmannite |
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| Outline of Final Research Achievements |
We attempted to construct structure models of ferrihydrite and schwertmannite based on the Z-contrast images obtained by scanning transmission electron microscopy. Particles identified as 6-line ferrihydrite by electron diffraction and X-ray diffraction have ABAC, AB, and irregular stacking sequences. Unlike the models previously proposed, Fe occupies octahedral holes, but little or no Fe occupies the tetrahedral holes. Schwertmannite has been thought to have a structure similar to akageneite, but in the Z-contrast images, tunnels made of Fe octahedrons like those in akageneite were not observed.
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| Free Research Field |
Mineralogy
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