Structural evolution of calcite at high temperatures: phase V unveiled.
Ontology highlight
ABSTRACT:
SUBMITTER: Ishizawa N
PROVIDER: S-EPMC3788374 | biostudies-literature | 2013
REPOSITORIES: biostudies-literature
Publications
Structural evolution of calcite at high temperatures: phase V unveiled.
Ishizawa Nobuo N Setoguchi Hayato H Yanagisawa Kazumichi K
Scientific reports 20131002
The calcite form of calcium carbonate CaCO₃ undergoes a reversible phase transition between Rc and Rm at ~1240 K under a CO₂ atmosphere of ~0.4 MPa. The joint probability density function obtained from the single-crystal X-ray diffraction data revealed that the oxygen triangles of the CO₃ group in the high temperature form (Phase V) do not sit still at specified positions in the space group Rm, but migrate along the undulated circular orbital about carbon. The present study also shows how the ro ...[more]
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