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Manganese oxide tunnel structures and their intergrowths
Science (New York, N.Y.)
|February 2, 1979
Summary
Natural hollandite and romanechite, common barium manganese minerals, show coherent intergrowths at the unit-cell level. High-resolution electron microscopy reveals complex structures within these manganese oxides.
Area of Science:
- Mineralogy
- Materials Science
- Geochemistry
Background:
- Hollandite and romanechite are prevalent barium-containing manganese minerals.
- Manganese oxides exhibit diverse and complex crystal structures.
- Understanding these structures is crucial for various applications.
Purpose of the Study:
- To investigate the microstructural relationships between natural hollandite and romanechite.
- To explore the structural complexities of manganese oxides using advanced imaging techniques.
Main Methods:
- High-resolution transmission electron microscopy (HRTEM) was employed.
- Microstructural analysis of mineral intergrowths was performed.
Main Results:
- Coherent intergrowths of hollandite and romanechite were observed at the unit-cell level.
- No apparent ordering was detected between the hollandite and romanechite structures within the intergrowths.
- Novel structures based on hollandite and romanechite frameworks were imaged.
Conclusions:
- Electron microscopy is essential for deciphering the intricate structures of manganese oxides.
- The study provides insights into the structural variability and intergrowth patterns of barium manganese minerals.
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