Energy transfer of highly vibrationally excited azulene. III. Collisions between azulene and argon

Abstract

The energy transfer dynamics between highly vibrationally excited azulene molecules (37 582 cm(-1) internal energy) and Ar atoms in a series of collision energies (200, 492, 747, and 983 cm(-1)) was studied using a crossed-beam apparatus along with time-sliced velocity map ion imaging techniques. The angular resolved collisional energy-transfer probability distribution functions were measured directly from the scattering results of highly vibrationally excited azulene. Direct T-VR energy transfer was found to be quite efficient. In some instances, nearly all of the translational energy is transferred to vibrational/rotational energy. On the other hand, only a small fraction of vibrational energy is converted to translational energy (V-T). Significant amount of energy transfer from vibration to translation was observed at large collision energies in backward and sideway directions. The ratios of total cross sections between T-VR and V-T increases as collision energy increases. Formation of azulene-argon complexes during the collision was observed at low enough collision energies. The complexes make only minor contributions to the measured translational to vibrational/rotational (T-VR) energy transfer.

Energy transfer of highly vibrationally excited naphthalene. II. Vibrational energy dependence and isotope and mass effects

“…[33][34][35][36][37]42,43 Only a brief description is described here. [33][34][35][36][37]42,43 Only a brief description is described here.…”

“…Some experimental results are available for comparison with the calculations. [34][35][36][37][38] The advantages of the crossed-beam experiments are that collisions are controlled to occur under a specific initial conditions, i.e., under single collision conditions at a given collision energy and at very low rotational temperature ͑Ͻ2 K͒. [27][28][29][30][31][32] The vibration energy relaxation of azulene by He, Ne, Ar, Kr, and Xe in a thermal system showed the mass effects, the average energy transfer of which increases from He, Ne, and Ar to Kr but levels off from Kr to Xe.…”

Competition between Photochemistry and Energy Transfer in UV-Excited Diazabenzenes. 4. UV Photodissociation of 2,3-, 2,5-, and 2,6-Dimethylpyrazine

“…In recent years, studies of energy transfer processes have focused, in particular, on understanding the energy transfer probability distribution function, P ( E , E ‘). − This function describes the probability that a molecule initially at energy E ‘ will, following a single collision event, have an energy E . A great deal of effort in energy transfer studies has also been expended to understand the role of “supercollisions”, − events in which a large amount of energy is transferred is a single collision, in relaxation processes.…”