Zirconium(IV) iodide 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 ...

with the formula Zr I₄. It is the most readily available iodide of zirconium. It is an orange-coloured solid that degrades in the presence of water. The compound was once prominent as an intermediate in the purification of zirconium metal.

Structure

Like most binary metal halides, zirconium(IV) iodide adopts a polymeric structure. As characterized by

X-ray crystallography X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles ...

, the compound consists of octahedral Zr(IV) centers interconnected by four doubly bridging iodide ligands. The Zr-I distances of 2.692 (terminal) and 3.030 Å

Synthesis and reactions

This compound is volatile, subliming as intact tetrahedral ZrI₄ molecules. It is prepared by the direct reaction of powdered zirconium metal and iodine..

Pyrolysis The pyrolysis (or devolatilization) process is the thermal decomposition of materials at elevated temperatures, often in an inert atmosphere. It involves a change of chemical composition. The word is coined from the Greek-derived elements ''py ...

of zirconium(IV) iodide gas by contact of hot wire was the first industrial process for the commercial production of pure ductile metallic zirconium. This

crystal bar process A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macrosc ...

was developed by

Anton Eduard van Arkel Anton Eduard van Arkel, (19 November 1893 – 14 March 1976) was a Dutch chemist. Van Arkel suggested the names "pnictogen" and "pnictide" to refer to chemical elements in group 15 (the nitrogen group or nitrogen family) of the periodic table. ...

and

Jan Hendrik de Boer Jan Hendrik de Boer (19 March 1899 – 25 April 1971) was a Dutch physicist and chemist. De Boer was born in Ruinen, De Wolden, and died in The Hague. He studied at the University of Groningen and was later employed in industry. Together with ...

in 1925.

References

Iodides Zirconium(IV) compounds Metal halides {{inorganic-compound-stub