Quasiclassical trajectory simulations of pyrazine-argon and methylpyrazine-argon van der Waals cluster predissociation and collisional energy transfer

Vibrational energy transfer in van der Waals cluster predissociation and in collisions between aromatic molecules (pyrazine and methylpyrazine) and ar gon was investigated by means of quasiclassical trajectory calculations. Th e calculated results for cluster predissociation show that only a small fra ction of the available vibrational energy is transferred to recoil energy, and the recoil energy distribution can be described by a smooth, roughly ex ponential function, in good agreement with experimental data [Yoder, L. M.; Barker, J. R. Phys. Chem. Chern. Phys. 2000, 2, 813]. The calculated colli sional step-size distributions are almost independent of temperature for T less than or equal to 300 K, but change in a complicated way for T > 300 K. It is also found that the cluster dissociation energy transfer distributio ns resemble those of low-temperature collisions.