MEYER, VIKTOR

born Sept. 8, 1848, Berlin died Aug. 8, 1897, Heidelberg, Baden German chemist who contributed greatly to knowledge of both organic and inorganic chemistry. Meyer studied under the analytic chemist Robert Bunsen, the organic chemist Emil Erlenmeyer, and the physicist Gustav Kirchhoff at the University of Heidelberg, where he received his Ph.D. in 1867 and where he later succeeded Bunsen (188997). Meyer earlier had served as professor of chemistry at the Zrich Polytechnic Institute (187285) and the University of Gttingen (188589). Devising a method of determining the vapour densities of inorganic substances at high temperatures (1871), Meyer found that diatomic molecules of iodine and bromine dissociate into atoms upon heating. In 1872 he discovered the aliphatic nitro compounds. Originator of the term stereochemistry, the study of molecules identical in chemical structure but possessing different spatial configurations (stereoisomers), Meyer discovered (1878) the oximes (organic compounds all containing the > C=NOH group) and demonstrated their stereoisomerism. He also coined the term steric hindrance to signify the energy barrier to rotation of different parts of an organic molecule brought about by the presence in the molecule of bulky side groups. A keen observer, he converted the failure of a lecture demonstration into his discovery (1882) of thiophene, a sulfur-containing organic compound resembling benzene in its chemical and physical properties.