Mode-specific decay widths in vibrational predissociation of D₂HF

In a recent paper, we employed a time-dependent golden rule method to calculate the decay widths for vibrational predissociation of D₂HF(υ=1) from the lowest van der Waals (vdW) state in both para and ortho cases. We examine the state dependence of the decay widths in D₂HF, by calculating the decay widths for a couple of excited van der Waals modes. It is shown that the total decay width is sensitive to the initial low frequency vdW state, while partial decay widths (final rotational state distribution) vary little for the initial states considered. It is discussed that excitation of the vdW stretching vibration, which characterizes the first excited state in both para- and ortho-D₂HF, is responsible for this mode sensitivity of the total decay width and the insensitivity of the partial decay widths.