Higher-order thermal motion tensor analysis and atom disorder in cubic melanophlogite
@article{Nakagawa2006HigherorderTM, title={Higher-order thermal motion tensor analysis and atom disorder in cubic melanophlogite}, author={Takeshi Nakagawa and Kuniaki Kihara}, journal={Journal of Mineralogical and Petrological Sciences}, year={2006}, volume={101}, pages={14-22} }
The structure of the high temperature form of melanophlogite (MEP) at 84 °C was refined by using a least squares refinement that was based on the Gram-Charlier expansion of the atomic probability density functions (PDF) up to the fourth-order terms. The refinements of 95 variable parameters on the space group Pm3n converged to R = 0.0275 (Rw = 0.0313) for the 607 observed reflections in single crystal X-ray diffraction. The PDFs for three types of O atom (in total, there were four types, O1 to…
6 Citations
X-ray studies of structural changes in melanophlogite with varying temperature
- Materials Science
- 2005
The a and c unit cell dimensions of melanophlogite (MEP) have been determined in the temperature range −50 to 700 °C, showing a different expansion behavior for the low temperature α-phase. The…
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Abstract The evolution with pressure of the CH4 vibrational modes related to C-H stretching has been followed by in situ Raman spectroscopy on a single crystal of cubic melanophlogite from Varano…
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Abstract The results of a new single-crystal structure refinement and of a Raman spectroscopy investigation on melanophlogite, a clathrate structure of SiO2, are reported. The studied sample comes…
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- Chemistry
- 2008
The results of a new single-crystal structure refinement and of a Raman spectroscopy investigation on melanophlogite, a clathrate structure of SiO2, are reported. The studied sample comes from a new…
Structural properties and phase transitions in a silica clathrate.
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