High-frequency Floquet theory: Test of the applicability of the golden rule

The high-frequency Floquet theory is applied to a particle bound by a Morse potential. Rates calculated in the acceleration frame with the golden rule for one- and two-photon dissociation are compared to those of an accurate multichannel resonance calculation. It is found that while the one-photon r ate is correctly determined by the golden rule, the two-photon above thresh old dissociation (ATD) is indirect (as in the length or velocity gauges). I t is induced by a continuum-continuum interaction and is not provided by a simple application of the golden rule. (C) 1999 John Wiley & Sons, Inc.