"CLASSICAL " QUANTUM CONTROL WITH APPLICATION TO SOLUTION REACTION DYNAMICS

Quantum control theory has the potential for great success in the ability to control the dynamics of gas phase molecules. Beyond 3 or 4 atoms, however, we are at present unable to compute the quantum dynamics needed to solve the control equations. An alternative applicable to larger systems, including polyatomics, clusters, surfaces, and condensed phases, is to approximate the quantum dynamics either classically or semiclassically. In this work, we present and illustrate a classical mechanical implementation of the weak field density matrix control theory. We consider I 2 wavepacket focusing in the gas phase and in Ar solution, comparing with full quantum calculations when possible. The classical calculations give results that are qualitatively similar to the full quantum calculations, and thereby show that the basic phenomenology of the control theory is accessible for more complex systems in a straightforward manner, in cases when purely quantum effects, such as tunnelling and interf..