Prepd by passing fluorine over iodine with cooling: Gore, Philos. Mag. [4] 41, 309 (1871); Moissan, Compt. Rend. 135, 563 (1902); Bull. Soc. Chim. Fr. [3] 29, 6 (1903); Ruff, Keim, Z. Anorg. Allg. Chem. 201, 245 (1931); Ruff, Braida, ibid. 220, 43 (1934); Kwasnik in Handbook of Preparative Inorganic Chemistry vol. 1, G. Brauer, Ed. (Academic Press, New York, 2nd ed., 1963) pp 159-160. Reviews: Kemmitt, Sharp, Adv. Fluorine Chem. 4, 247-248 (1965); Stein, “Physical and Chemical Properties of Halogen Fluorides” in Halogen Chemistry Vol. 1, V. Gutmann, Ed. (Academic Press, New York, 1967) pp 133-224; Meinert, Z. Chem. 7, 41-57 (1967).