Dipartimento di Chimica, Università degli Studi di Sassari and Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali (INSTM), Unità di Ricerca di Sassari, via Vienna, 2, I-07100 Sassari, Italy.
J Chem Phys. 2011 Sep 28;135(12):124110. doi: 10.1063/1.3643764.
We applied a method based on a block cellular automaton (BCA) algorithm to the study of diffusion of various binary mixtures adsorbed in a model microporous material, such as zeolite ZK4. Our aim was to test the capability of our model to cope with systems in which more than one species is present, using a set of parameters based on heuristic considerations from the molecular dynamics (MD) results present in the literature. A rigorous methodology for the assignment of suitable adsorption energies and diffusion activation barriers for our BCA has not been developed yet, nonetheless the results were quite interesting at this stage and we obtained a good qualitative agreement with MD data in the literature. The mixtures we investigated contain CO(2), which causes the so-called segregation-effect, a strong suppression of self-diffusivity of co-adsorbed species. This effect gives rise to relevant problems in the application of some well established and robust methods, while our model proved to be able to reproduce both the common features and the segregation anomaly in the trends of diffusion.
我们应用基于块细胞自动机（BCA）算法的方法研究了各种二元混合物在模型微孔材料（如沸石 ZK4）中的吸附扩散。我们的目的是使用一组基于文献中分子动力学（MD）结果的启发式考虑的参数来测试我们的模型处理存在多种物质的系统的能力。尚未开发出用于为我们的 BCA 分配合适的吸附能和扩散激活势垒的严格方法，尽管在现阶段结果非常有趣，并且我们与文献中的 MD 数据取得了很好的定性一致。我们研究的混合物含有 CO(2)，这会导致所谓的分凝效应，强烈抑制共吸附物质的自扩散。这种效应在应用一些成熟且稳健的方法时会引发相关问题，而我们的模型被证明能够再现扩散趋势中的共同特征和分凝异常。
