X‐ray and neutron investigations of the P–I transition in pure anorthite

摘要: The temperature dependence of sharp and diffuse c d reflections in pure anorthite was investigated by X-ray neutron measurements from room up to 700 K. At 513 ± 4 K a complete, reversible continuous phase transition P{\bar 1}-I{\bar 1} can be observed. Here the scattering reaches maximum. It has remarkable anisotropy along b* (a* - b*) directions. All experimental findings as well formation an antiphase domain structure explained simple dynamical model.