화학공학소재연구정보센터
Journal of the American Chemical Society, Vol.136, No.5, 1682-1685, 2014
Chemical Activation through Super Energy Transfer Collisions
Can a molecule be efficiently activated with a large amount of energy in a single collision with a fast atom? If so, this type of collision will greatly affect molecular reactivity and equilibrium in systems where abundant hot atoms exist. Conventional expectation of molecular energy transfer (ET) is that the probability decreases exponentially with the amount of energy transferred, hence the probability of what we label "super energy transfer" is negligible. We show, however, that in collisions between an atom and a molecule for which chemical reactions may occur, such as those between a translationally hot H atom and an ambient acetylene (HCCH) or sulfur dioxide, ET of chemically significant amounts of energy commences with surprisingly high efficiency through chemical complex formation. Time-resolved infrared emission observations are supported by quasi-classical trajectory calculations on a global ab initio potential energy surface. Results show that similar to 10% of collisions between H atoms moving with similar to 60 kcal/mol energy and HCCH result in transfer of up to 70% of this energy to activate internal degrees of freedom.