Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
Iodine heptafluoride
Introduction
Iodine heptafluoride, also known as iodine(VII) fluoride or even iodine fluoride, is the compound IF7 [1] [2]. It has an unusual pentagonal bipyramidal structure, as predicted by VSEPR theory.[3] The molecule can undergo a pseudorotational rearangment like the Berry mechanism but for a hepta coordinated system. [4] It forms colorless 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 moldy, acrid odor.
Preparation
Preparation
IF7 is prepared by passing F2 through liquid IF5 at 90 °C, then heating the vapors to 270 °C. Alternately, this compound can be prepared from fluorine and dried PdI2 or KI to minimize the formation of IOF5, an impurity arising by hydrolysis.[5] [6]
Safety considerations
Safety considerations
IF7 is highly irritating to both the skin and the mucous membranes.
References
References
- ↑ Macintyre, J. E. (Ed.). (1992). Dictionary of Inorganic Compounds (Vol. 3). London: Chapman & Hall.
- ↑ O’Neil, Maryadele J. (Ed.). (2001). The Merck Index (13th ed.). Whitehouse Station, NJ: Merck.
- ↑ K. O. Christe, E. C. Curtis, D. A. Dixon (1993). “On the problem of heptacoordination: vibrational spectra, structure, and fluxionality of iodine heptafluoride”. Industrial & Engineering Chemistry. 115 (4): 1520–1526. doi:10.1021/ja00057a044.
- ↑ W. J. Adams, H. Bradford Thompson, L. S. Bartell (1970). “Structure, Pseudorotation, and Vibrational Mode Coupling in IF7: An Electron Diffraction Study”. Journal of Chemical Physics. 53 (10): 4040–4046. doi:10.1063/1.1673876.
- ↑ W. C. Schumb, M. A. Lynch, Jr. (1950). “Iodine Heptafluoride”. Industrial & Engineering Chemistry. 42 (7): 1383–1386. doi:10.1021/ie50487a035.
- ↑ Ruff O., Keim R. (1930). ““Das Jod-7-fluorid” (The iodine-7-fluoride)”. Zeitschrift für Anorganische un Allgemeine Chemie. 193 (1/2): 176–186. doi:10.1002/zaac.19301930117.