Determination of space groupPncm of prehnite using electron diffraction method

Abstract

Space symmetry of prehnite, which occurs in cavities and veins within Skarn from the Tieshan iron mineral deposit, Daye, Hubei province, Central China, has been determined using selected area electron diffraction (SAED) and convergent-beam electron diffraction (CBED) on the submicrometer scale. Our results confirm that the natural prehnite may have the structure with symmetry Pncm. The unit-cell parameters of investigated prehnite (a=0.458 nm, b=0.555 nm, and c=1.853 nm) have been calculated by using the multicrystal diffraction rings of gold, the internal standard.

Keywords

prehnite / Pncm / selected area electron diffraction / convergent-beam electron diffraction

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