Regular hexagonal-prism microvoids in CeF3 single crystals

Microvoids are well-known crystal defects, usually exhibiting a rounded and/or irregular shape, which act as undesired scattering centers in optical applications. Here, for the first time, residual micmvoids in the shape of perfect regular hexagonal-prisms are observed in apparently scattering-free CeF(3)( )bulk single crystals. These microvoids reflect exactly the natural crystal habit in negative form: the prisms stand along the c-axis and the hexagonal sides are parallel to the six equivalent planes perpendicular to the a-axis. They distribute randomly with sizes up to 13 mu m and heights in the submicron order with a maximum around 500 nm. The micmvoids are formed by the embedding of bubbles during the crystallization process. The bubbles' gas is possibly caused by the high vapor pressure of CeF3 itself at the high melting point.

Automated summary

Microvoids, well-known crystal defects, were observed for the first time in apparently scattering-free CeF(3) bulk single crystals, taking on the shape of perfect regular hexagonal-prisms. These microvoids are formed by the embedding of bubbles during the crystallization process, with sizes up to 13 mu m and heights in the submicron order.