The HgI2 single crystal with few large smooth faces, high quality and
360 g in weight has been grown by a new technique of modified vapour p
hase located point method, and the growth characteristics of HgI2 sing
le crystals have been investigated in detail It is found by means of X
-ray diffraction that the crystals grown with the c-axis parallel or p
erpendicular to the pedestal plane have both the prism faces {110}.