Coherent and dissipative wave packet dynamics in cyclic model systems with four equivalent potential minima

The dynamics of cyclic systems with four equivalent potential minima is studied here from two different points of view. The solution of the time‐dependent Schrodinger equation provides insight into the coherent wave packet motion. The resulting reaction mechanism involves relocalization between opposite, not neighboring potential minima. The inclusion of an environment within a density matrix description leads to dissipation and therefore to a transition from coherent to incoherent dynamics. The theoretical considerations are applied to a simple model of the cyclic motion of a proton in a molecular framework.