Americium(III) iodide or americium triiodide is the chemical compound, a salt composed of americium and iodine with the formula AmI<sub>3</sub>.
Americium(III) iodide can be prepared by reacting americium(III) chloride with ammonium iodide:
Americium(III) iodide takes the form of yellow crystals. The crystal form is orthorhombic. It melts around 960 ðC. The density is 6.9 g/cm<sup>3</sup>. The compound consists of Am<sup>3+</sup> and I<sup>âÂÂ</sup> ions. It crystallizes in the trigonal crystal system in the space group R (space group no. 148) with the lattice parameters a = 742 pm and c = 2055 pm and six formula units per unit cell. Its crystal structure is isotypic with bismuth(III) iodide.