The. ??? ???Enantiodifferentiation by NMR, modelling, and other applications???, Molecules which are identical (superimposable) with their mirror image geometries are always optically This includes E/Z-isomers of alkenes which may be regared as configurational isomers (not interconvertible through rotation about C-C single bonds), and which are not superimposable to each other. ??? ???PD Dr. Stefa