Aromatic transition state theory

The Aromatic transition state theory assumes that the minimum energy transition state for a pericyclic process must be aromatic. For 4n+2 π sysyems (2,6,10...) Huckel transition states are proposed where the molecule is flat. In 4n π sysyems (4,8,12...) Mobius transition states are proposed which involve a twist or require a node to be aromatic.