Yin Cangtao, Czakó Gábor
MTA-SZTE Lendület Computational Reaction Dynamics Research Group, Interdisciplinary Excellence Centre and Department of Physical Chemistry and Materials Science, Institute of Chemistry, University of Szeged, Rerrich Béla tér 1, Szeged, Hungary.
Commun Chem. 2024 Jul 13;7(1):157. doi: 10.1038/s42004-024-01237-9.
Criegee intermediates play an important role in the tropospheric oxidation models through their reactions with atmospheric trace chemicals. We develop a global full-dimensional potential energy surface for the CHOO + SO system and reveal how the reaction happens step by step by quasi-classical trajectory simulations. A new pathway forming the main products (CHO + SO) and a new product channel (CO + H + SO) are predicted in our simulations. The new pathway appears at collision energies greater than 10 kcal/mol whose behavior demonstrates a typical barrier-controlled reaction. This threshold is also consistent with the ab initio transition state barrier height. For the minor products, a loose complex OCHO ∙ ∙ ∙ SO is formed first, and then in most cases it soon turns into HCOOH + SO, in a few cases it decomposes into CO + H + SO which is a new product channel, and rarely it remains as ∙OCHO ∙ + SO.
克里吉中间体通过与大气痕量化学物质的反应在对流层氧化模型中发挥着重要作用。我们为CHOO + SO体系构建了一个全球全维势能面，并通过准经典轨迹模拟揭示了反应是如何一步步发生的。在我们的模拟中预测了一条形成主要产物（CHO + SO）的新途径和一个新的产物通道（CO + H + SO）。新途径出现在碰撞能量大于10千卡/摩尔时，其行为表现出典型的势垒控制反应。这个阈值也与从头算过渡态势垒高度一致。对于次要产物，首先形成一个松散的复合物OCHO∙∙∙SO，然后在大多数情况下它很快转化为HCOOH + SO，在少数情况下它分解为CO + H + SO，这是一个新的产物通道，很少情况下它会保持为∙OCHO∙ + SO。
