Bal Kristof M, Neyts Erik C
Department of Chemistry , University of Antwerp , Universiteitsplein 1 , 2610 Antwerp , Belgium . Email:
Chem Sci. 2016 Aug 1;7(8):5280-5286. doi: 10.1039/c6sc00498a. Epub 2016 May 5.
Atomistic simulations can in principle provide an unbiased description of all mechanisms, intermediates, and products of complex chemical processes. However, due to the severe time scale limitation of conventional simulation techniques, unrealistically high simulation temperatures are usually applied, which are a poor approximation of most practically relevant low-temperature applications. In this work, we demonstrate the direct observation at the atomic scale of the pyrolysis and oxidation of -dodecane at temperatures as low as 700 K through the use of a novel simulation technique, (CVHD). A simulated timescale of up to 39 seconds is reached. Product compositions and dominant mechanisms are found to be strongly temperature-dependent, and are consistent with experiments and kinetic models. These simulations provide a first atomic-level look at the full dynamics of the complicated fuel combustion process at industrially relevant temperatures and time scales, unattainable by conventional molecular dynamics simulations.
原则上,原子模拟可以对复杂化学过程的所有机制、中间体和产物进行无偏差描述。然而,由于传统模拟技术存在严重的时间尺度限制,通常会采用不切实际的高模拟温度,这对于大多数实际相关的低温应用而言是很差的近似。在这项工作中,我们通过使用一种新颖的模拟技术(CVHD),展示了在低至700 K的温度下对正十二烷热解和氧化过程进行原子尺度的直接观察。达到了高达39秒的模拟时间尺度。发现产物组成和主要机制强烈依赖于温度,并且与实验和动力学模型一致。这些模拟首次在原子水平上展现了在工业相关温度和时间尺度下复杂燃料燃烧过程的完整动力学,这是传统分子动力学模拟无法实现的。