History of fluorine reaction. Scheele recognized the product of the reaction as an acid, which he called "fluss-spats-syran" (fluor-spar-acid); in English, it was known as "fluoric acid". In 1810, French physicist André-Marie Ampère suggested that hydrofluoric acid was a compound of hydrogen with an unknown element, analogous to chlorine. Fluorite was then shown to be mostly composed of calcium fluoride. Sir Humphry Davy originally suggested the name "fluorine", taking the root from the name of "fluoric acid" and the -ine suffix, similarly to other halogens. This name, with modifications, came to most European languages. (Greek, Russian, and several other languages use the name
Graphite intercalation compound A stage n magnetic GIC has n graphite layers separating successive magnetic layers. As the stage number increases the interaction between spins in successive magnetic layers becomes weaker and 2D magnetic behaviour may arise. Chlorine and bromine reversibly intercalate into graphite. Iodine does not. Fluorine reacts irreversibly. In the case of bromine, the following stoichiometries are known: CBr for n = 8, 12, 14, 16, 20, and 28. Because it forms irreversibly, carbon monofluoride is often not classified as an intercalation compound. It has the formula (CF). It is prepared by reaction of gaseous fluorine with graphitic carbon at 215–230