X-ray studies of structural changes in melanophlogite with varying temperature

@article{Nakagawa2005XraySO,
  title={X-ray studies of structural changes in melanophlogite with varying temperature},
  author={Takeshi Nakagawa and Kuniaki Kihara and Syuhei Fujinami},
  journal={Journal of Mineralogical and Petrological Sciences},
  year={2005},
  volume={100},
  pages={247-259}
}
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 c-axis length, 2c, which is smaller than a-axis length in the α-phase, shows a steep rise reaching the value of a at the tetragonal (α)-cubic (β) transition temperature at about 65 °C, and then remains nearly constant until about 500 °C, after which contraction occurs. The crystal structures of α-MEP… 
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