Asymmetry sum rule for molecular predissociation - art. no. 012513

In the case of weak diatomic molecular predissociation by noninteracting, o ptically inactive continuum states, it is demonstrated that the predissocia tion line shape is more accurately represented by a Beutler-Fano profile th an by a Lorentzian. The weak asymmetry that is found to occur is due princi pally to interactions with neighboring vibrational resonances. For this typ e of predissociation in the case of multiple continua, a sum rule for the c orresponding line-shape asymmetry is derived. This sum rule is verified num erically using single channel and multichannel coupled Schrodinger-equation calculations for the Schumann-Runge band system of O-2. Similar results ar e presented for the case of optically active continua.