THE ROLE OF A MOLECULAR-PHASE IN 2-PATHWAY EXCITATION SCHEMES

The origin and potential implications of a molecular phase in coherent two-pathway excitation are analyzed by means of a time-independent, q uantum mechanical theory. A unified model is developed describing unim olecular decay into several continua of general nature, where each bre akup reaction takes place both directly and via a manifold of resonanc es. It is found that the molecular phase, observable in two pathway ex citation experiments, correlates with the single-pathway fragmentation line shape, in agreement with recent measurements. We propose the mea surement of molecular phases as a route to molecular properties which are silent in conventional observables. (C) 1998 American Institute of Physics.