Abbreviations used throughout the manuscript for the five PbI2 products, arranged according to measured stoichiometry, are shown in Table , along with their nominal purity, physical form, I:Pb ratio, and impurity information inferred from our data. The nomenclature is based on the supplier name and the number of "9s" in the quoted purity using metals basis or trace metals basis when reported. Perfectly pure, stoichiometric PbI2 should display an I:Pb ratio equal to two; therefore, stoichiometry is suggestive of overall purity or quality, but might not be predictively reliable.