Sodium Iodide Crystal

NaI is soluble in water and other solvents with solubility of 179 g/100 g H2O (20℃), 43 g/100 g C2H5OH (23℃), and 78 g/100 g CH3OH (23℃). NaI is used for the research of impurities etc., because of wide forbidden band of phonon energy similar to KI. The NaI crystal slightly doped with Tl shows the high sensibility for the radiation detector.

Crystal System

The space lattice of NaI belongs to the cubic system, and its rock salt structure has a lattice constant of a=0.6462 nm and Na–I=0.325 nm. NaI·2H2O with monoclinic system and specific gravity of 2.45 is grown from the solution, which transforms to NaI above the transition temperature 658C and to NaI·5H2O at K13.5 to K31.5℃.

Production

A single crystal is grown from the melt solution by the Kyropoulos method or the Stockbarger method. The glass or the porcelain crucible is available.