Molybdenum(III) iodide is the
inorganic compound
In chemistry, an inorganic compound is typically a chemical compound that lacks carbon–hydrogen bonds, that is, a compound that is not an organic compound. The study of inorganic compounds is a subfield of chemistry known as '' inorganic chemi ...
with the formula MoI
3.
Preparation
Molybdenum(III) iodide is created by the reaction of
molybdenum hexacarbonyl
Molybdenum hexacarbonyl (also called molybdenum carbonyl) is the chemical compound with the formula Mo(CO)6. This colorless solid, like its chromium and tungsten analogues, is noteworthy as a volatile, air-stable derivative of a metal in its zero ...
with
iodine
Iodine is a chemical element with the Symbol (chemistry), symbol I and atomic number 53. The heaviest of the stable halogens, it exists as a semi-lustrous, non-metallic solid at standard conditions that melts to form a deep violet liquid at , ...
gas at .
:2 Mo(CO)
6 + 3 I
2 → 2 MoI
3 + 12 CO
It can also be made from
molybdenum(V) chloride
Molybdenum(V) chloride is the inorganic compound with the empirical formula . This dark volatile solid is used in research to prepare other molybdenum compounds. It is moisture-sensitive and soluble in chlorinated solvents.
Structure
Usually call ...
and a solution of
hydrogen iodide
Hydrogen iodide () is a diatomic molecule and hydrogen halide. Aqueous solutions of HI are known as hydroiodic acid or hydriodic acid, a strong acid. Hydrogen iodide and hydroiodic acid are, however, different in that the former is a gas under s ...
in
carbon disulfide
Carbon disulfide (also spelled as carbon disulphide) is a neurotoxic, colorless, volatile liquid with the formula and structure . The compound is used frequently as a building block in organic chemistry as well as an industrial and chemical ...
.
:MoCl
5 + 5 HI → MoI
3 + 5 HCl + I
2
A further method is direct reaction between molybdenum metal and excess iodine at .
:2 Mo + 3 I
2 → 2 MoI
3
As molybdenum(III) iodide is the highest stable iodide of molybdenum, this is the preferred route.
Properties
Molybdenum(III) iodide is a black
antiferromagnetic
In materials that exhibit antiferromagnetism, the magnetic moments of atoms or molecules, usually related to the spins of electrons, align in a regular pattern with neighboring spins (on different sublattices) pointing in opposite directions. ...
solid that is air-stable at room temperature. In vacuum, it decomposes above 100 °C to molybdenum(II) iodide and iodine. It is insoluble in polar and non-polar solvents.
Its crystal structure is isotypic with zirconium(III) iodide.
References
Momlybdenum triiodide at Web Elements
Iodides
Molybdenum halides
Molybdenum(III) compounds
{{Inorganic-compound-stub