Hans-Werner Wanzlick
Introduction '''Hans-Werner Wanzlick''' (1917-1988) was a German chemist. A Professor of chemistry at the Berlin Technical University he  is notable for work on persistent carbenes and for proposing the Wanzlick equilibrium between saturated imidazolin-2-ylidenes and their dimers  — which he called "''das doppelte Lottchen''", after a 1949 novel by Erich Kästner about a pair of mischievous twins.
References * Hans-Werner Wanzlick (1958), letter to Linus Pauling (in German). Linus Pauling's Correspondence, item #444.6.