The crystal structure of low melanophlogite

  title={The crystal structure of low melanophlogite},
  author={Takeshi Nakagawa and Kuniaki Kihara and Kazuoki Harada},
  journal={American Mineralogist},
  pages={1506 - 1512}
Abstract The crystal structure of the low temperature form of natural melanophlogite, 46SiO2 · 6M14 · 2M12 (M14 = N2, CO2; M12 = CH4, N2), was determined using single-crystal X-ray diffraction data at room temperature. The structure is tetragonal with space group P42/nbc and unit cell a = 26.818(2) and c = 13.365(1) Å, which is the (2 × 2 × 1) superstructure of high-temperature cubic melanophlogite and includes four formula units. The structure with 335 variable parameters including anisotropic… 

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