Jay E. Taylor

Efficiencies in the Exchange of Translational and Vibrational Energies in Cyclopropane‐Argon Mixtures

The velocity dispersions in cyclopropane‐argon mixtures are investigated as a means of characterizing the repulsive parameters both for cyclopropane and argon. It is found that the removal of energy from a vibrationally excited cyclopropane is more efficiently accomplished by another cyclopropane molecule than by an argon atom. Since there is virtually no mass effect in comparing the probabilities of translation‐vibration energy exchange for cyclopropane‐argon and cyclopropane‐cyclopropane encounters, the difference is attributed to a steeper intermolecular potential in the case of cylcopropane self‐collisions. Quantitative results are obtained by comparing the experimental values with those from the equation of Herzfeld and Litovitz.

Steric Effects in the Translation‐Vibration Energy Transfer in Cyclopropane‐Inert Encounters

The data for a study of steric effects in the exchange of translational and vibrational energies are provided by the velocity dispersions in cyclopropane‐inert mixtures at 307.0°K. With helium, neon, and argon as projectiles and cyclopropane as the target, a comparison of the experimental results with results from the theoretical equation of Herzfeld and Litovitz is used to determine the dependence of the probability of energy transfer on the size of these atoms. The apparent variation of the interchange of translational and vibrational energy between molecules as a function of molecular size is explained by the assumption of active sites on the cyclopropane molecule.