Dimer (chemistry) dimerise to give the dimer "A-A". An example is a diaminocarbene, which dimerise to give a tetraaminoethylene: Carbenes are highly reactive and readily form bonds. Dicyclopentadiene is an asymmetrical dimer of two cyclopentadiene molecules that have reacted in a Diels-Alder reaction to give the product. Upon heating, it "cracks" (undergoes a retro-Diels-Alder reaction) to give identical monomers: Many nonmetallic elements occur as dimers: hydrogen, nitrogen, oxygen, the halogens, i.e. fluorine, chlorine, bromine and iodine. Noble gases can form dimers linked by van der Waals bonds, for example dihelium or diargon. Mercury occurs as a mercury(I) cation (Hg), formally a dimeric
Chlorine pentafluoride with water to produce chloryl fluoride and hydrogen fluoride: It is also a strong fluorinating agent. At room temperature it reacts readily with all elements (including otherwise "inert" elements like platinum and gold) except noble gases, nitrogen, oxygen and fluorine. Chlorine pentafluoride Chlorine pentafluoride is an interhalogen compound with formula ClF. This colourless gas is a strong oxidant that was once a candidate oxidizer for rockets. The molecule adopts a square pyramidal structure with C symmetry, as confirmed by its high-resolution F NMR spectrum. Some of the earliest research on the preparation was classified. It was first prepared by fluorination