Iodine 1% of a sample of gaseous iodine at atmospheric pressure is dissociated into iodine atoms at 575 °C. Temperatures greater than 750 °C are required for fluorine, chlorine, and bromine to dissociate to a similar extent. Most bonds to iodine are weaker than the analogous bonds to the lighter halogens. Gaseous iodine is composed of I molecules with an I–I bond length of 266.6 pm. The I–I bond is one of the longest single bonds known. It is even longer (271.5 pm) in solid orthorhombic crystalline iodine, which has the same crystal structure as chlorine and bromine. (The record is
Bromine pentafluoride Bromine pentafluoride Bromine pentafluoride, BrF, is an interhalogen compound and a fluoride of bromine. It is a strong fluorination reagent. BrF finds use in oxygen isotope analysis. Laser ablation of solid silicates in the presence of bromine pentafluoride releases O for subsequent analysis. It has also been tested as an oxidizer in liquid rocket propellants and is used as a fluorinating agent in the processing of uranium. Bromine pentafluoride was first prepared in 1931 by the direct reaction of bromine with fluorine. This reaction is suitable for the preparation of large quantities, and is carried out at temperatures over with