Synthesis and Ultrapurification of Tin Diiodide

This paper presents results of a study aimed at developing physicochemical principles of tin diiodide (SnI2) synthesis and ultrapurification by high-temperature fractional distillation. SnI2 samples were synthesized by different processes: in solution, from elemental mixtures at atmospheric pressure, and in a vacuum. Next, the samples were purified by fractional distillation in a plate column. Separation factors of difficult-to-remove impurities in the SnI2-based liquid–vapor system have been determined experimentally. We have prepared and characterized extrapure-grade SnI2 containing 10 ppm by weight of trace impurities