IF7

Iodine heptafluoride

Names
Other names Iodine(VII) fluoride Heptafluoroiodine
Identifiers
CAS Number	16921-96-3 Y
3D model (Jmol)	Interactive image
ChemSpider	21477354 Y
ECHA InfoCard	100.037.241
PubChem CID	85645
InChI InChI=1S/F7I/c1-8(2,3,4,5,6)7 Y Key: XRURPHMPXJDCOO-UHFFFAOYSA-N Y InChI=1/F7I/c1-8(2,3,4,5,6)7 Key: XRURPHMPXJDCOO-UHFFFAOYAO
SMILES FI(F)(F)(F)(F)(F)F
Properties
Chemical formula	IF7
Molar mass	259.90 g/mol
Appearance	colorless gas
Density	2.6 g/cm3 (6 °C) 2.7 g/cm3 (25 °C)
Melting point	4.5 °C (40.1 °F; 277.6 K) (triple point)
Boiling point	4.8 °C (40.6 °F; 277.9 K) (sublimes at 1 atm)
Solubility in water	soluble
Related compounds
Related compounds	iodine pentafluoride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Iodine heptafluoride, also known as iodine(VII) fluoride or iodine fluoride, is an interhalogen compound with the chemical formula IF₇. It has an unusual pentagonal bipyramidal structure, as predicted by VSEPR theory. The molecule can undergo a pseudorotational rearrangement called the Bartell mechanism, which is like the Berry mechanism but for a heptacoordinated system. It forms colourless crystals, which melt at 4.5 °C: the liquid range is extremely narrow, with the boiling point at 4.77 °C. The dense vapor has a mouldy, acrid odour. The molecule has D_5h symmetry.

IF₇ is prepared by passing F₂ through liquid IF₅ at 90 °C, then heating the vapours to 270 °C. Alternatively, this compound can be prepared from fluorine and dried palladium or potassium iodide to minimize the formation of IOF₅, an impurity arising by hydrolysis.

IF₇ is highly irritating to both the skin and the mucous membranes. It also is a strong oxidizer and can cause fire on contact with organic material.