Friedrich August Kekulé (von Stradonitz) is the…

Friedrich August Kekulé (von Stradonitz) is the principal formulator of the theory of chemical structure.

Basing his ideas on those of predecessors such as Alexander William Williamson, Edward Frankland, William Odling, Charles Adolphe Wurtz and others, Kekulé's theory proceeds from the idea of atomic valence, especially the tetravalence of carbon (which Kekulé had announced late in 1857) and the ability of carbon atoms to link to each other (which he announces in May 1858), to the determination of the bonding order of all of the atoms in a molecule

Privatdozent at the University of Heidelberg from 1856, Kekulé, an organic chemist, is hired as full professor at the University of Ghent in 1858.