CONTROVERSY AND COMPLEMENTARITY IN MECHANISTIC ORGANIC-CHEMISTRY - THE TRANSITION-STATE AND STRUCTURAL THEORIES REEXAMINED

It is proposed that molecular phenomena may only be described within t he framework of the Complementarity Principle ('CP'), and that scienti fic controversy may originate in the essential incompatibility of comp lementary representations. Complementarity based on the temporal Uncer tainty Principle leads to new insights into transition state theory, m icroscopic reversibility and the Curtin-Hammett Principle. An empirica l application of the 'CP' to the structural theory leads to a revision of present concepts of 'reaction dynamics', with the Principle of Lea st Nuclear Motion ('PLNM') emerging as a general alternative to electr onic theories of reactivity. In fact, it is argued that the 'PLNM' is a better basis for the Woodward-Hoffmann rules than is orbital symmetr y. A more flexible approach to organic reaction mechanisms is thus ind icated. Also, as the basis of the structural theory is fundamentally u ncertain, and the present theory of X-ray diffraction apparently incom patible with the 'UP', a reinterpretation of the Bragg equation has be en attempted.