On the Separation of Timescales in Chemically Activated Reactions

摘要: Chemically activated reactions are important in describing the composition of reactive gases including flames, planetary atmospheres, and interstellar medium (ISM). In a chemically reaction, two reactants combine to populate vibrationally excited well that can undergo unimolecular transformations (isomerization, dissociation) or be thermalized through collisions with bath gas. Once has been thermalized, it may still have sufficient energy further purely thermal process. If timescale for thermally process is sufficiently short, such approaches concurrent processes become inseparable value phenomenological rate coefficient no longer obvious. Here, we introduce decay (TD) procedure determine coefficients proceeding on timescales approaching those principally use stochastic master equation simulations multiple-well multiple-channel reaction processes. By fitting initially first-order kinetic model, would-be yield eliminated so as arrive at component reliable objective fashion. This technique demonstrated here 1,3,6-heptatriyne H using MultiWell code 16-well 33-channel C7H5 model. A computer program implementing TD method postprocessing output data, PPM, provided.