Diffusion of isobutane in silicalite: a neutron spin-echo and molecular dynamics simulation study
Diffusion of isobutane in silicalite: a neutron spin-echo and molecular dynamics simulation study
复制标题
异丁烷在硅沸石中的扩散：中子自旋回波和分子动力学模拟研究
DOI：
10.1021/acs.jpcc.5b08048
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发表时间：
2015
影响因子：
3.7
通讯作者：
H. Jobic
中科院分区：
文献类型：
--
作者：
Alexander J. O’Malley;C. R. Catlow;M. Monkenbusch;H. Jobic
在444~550K温度范围内，用中子自旋回波实验和分子动力学模拟研究了异丁烷在硅沸石中的扩散。实验和模拟的扩散系数在一个数量级内符合得很好，扩散活化能在3.4kJmol-L(∼15%)以内。NSE以10A的跳跃距离观察到跳跃扩散，MD模拟也观察到滞留时间花费在正弦通道的一小部分，而不是以前的模拟所报道的通道之间的交叉点。如NSE实验所观察到的，在模拟中，正弦捕获水平随着温度的升高而减小，其中异丁烷在两个通道系统中发展各向同性扩散。
The diffusion of isobutane in silicalite was studied using neutron spin–echo (NSE) experiments and molecular dynamics (MD) simulations between 444 and 550 K. The experimental and simulated diffusion coefficients showed agreement well within an order of magnitude, as did the activation energies of diffusion which agreed to within 3.4 kJ mol–l (∼15%). Jump diffusion was observed by NSE with a jump distance of 10 A, also observed by the MD simulations showing that the residence time was spent in a small section of the sinusoidal channel, rather than the intersections between channels as reported in previous simulations. The level of sinusoidal trapping diminishes in the simulations with increasing temperature, where the isobutane develops isotropic diffusion through both channel systems, as observed by NSE experiments.