Americium(III) iodide or americium triiodide is the

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

, a salt composed of

americium Americium is a synthetic element, synthetic chemical element; it has Chemical symbol, symbol Am and atomic number 95. It is radioactive and a transuranic member of the actinide series in the periodic table, located under the lanthanide element e ...

and

iodine Iodine is a chemical element; it has symbol I and atomic number 53. The heaviest of the stable halogens, it exists at standard conditions as a semi-lustrous, non-metallic solid that melts to form a deep violet liquid at , and boils to a vi ...

with the

formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwe ...

AmI₃.

Preparation

Americium(III) iodide can be prepared by reacting

americium(III) chloride Americium(III) chloride or americium trichloride is the chemical compound composed of americium and chlorine with the formula AmCl3. This salt forms pink hexagonal crystals. In the solid state each americium atom has nine chlorine atoms as near ne ...

with

ammonium iodide Ammonium iodide is the inorganic compound with the formula NH4I. A white solid. It is an ionic compound, although impure samples appear yellow. This salt consists of ammonium cation and an iodide anion.Holleman, A. F.; Wiberg, E. ''Inorganic Chemis ...

: :

Properties

Americium(III) iodide takes the form of yellow crystals. The crystal form is

orthorhombic In crystallography, the orthorhombic crystal system is one of the 7 crystal systems. Orthorhombic Lattice (group), lattices result from stretching a cubic crystal system, cubic lattice along two of its orthogonal pairs by two different factors, res ...

. It melts around 960 °C. The density is 6.9 g/cm³. The compound consists of Am³⁺ and I⁻ ions. It crystallizes in the

trigonal crystal system In crystallography, the hexagonal crystal family is one of the six crystal families, which includes two crystal systems (hexagonal and trigonal) and two lattice systems (hexagonal and rhombohedral). While commonly confused, the trigonal crystal ...

in the

space group In mathematics, physics and chemistry, a space group is the symmetry group of a repeating pattern in space, usually in three dimensions. The elements of a space group (its symmetry operations) are the rigid transformations of the pattern that ...

R (space group no. 148) with the

lattice parameter A lattice constant or lattice parameter is one of the physical dimensions and angles that determine the geometry of the unit cells in a crystal lattice, and is proportional to the distance between atoms in the crystal. A simple cubic crystal has ...

s a = 742 pm and c = 2055 pm and six formula units per unit cell. Its crystal structure is isotypic with

bismuth(III) iodide Bismuth(III) iodide is the inorganic compound with the formula Bi I3. This gray-black salt is the product of the reaction of bismuth and iodine, which once was of interest in qualitative inorganic analysis. Bismuth(III) iodide adopts a distin ...

.''

Gmelins Handbuch der anorganischen Chemie The Gmelin database is a large database of organometallic and inorganic compounds updated quarterly. It is based on the German publication ''Gmelins Handbuch der anorganischen Chemie'' ("Gmelin's Handbook of Inorganic Chemistry") which was original ...

'', System No. 71, Transurane, Teil C, pp. 154.

References

Americium compounds Iodides Actinide halides {{inorganic-compound-stub