Polyakov Pavel, Rossinsky Eddie, Wiegand Simone
Forschungszentrum Julich GmbH, IFF - Weiche Materie, D-52428 Julich, Germany.
J Phys Chem B. 2009 Oct 8;113(40):13308-12. doi: 10.1021/jp904667p.
We studied the thermal diffusion behavior of equimolar mixtures of hydrocarbon chains in cyclohexane, p-xylene, and o-xylene experimentally and by reverse nonequilibrium molecular dynamics. The hydrocarbon chains heptane, 2,3-dimethylpentane, 2,4-dimethylpentane, 2-ethyl-3-methyl butadiene, and 2,4-dimethylpentadiene-1,3 with the same number of carbon atoms were considered in order to conserve the mass contribution and to investigate the shape influence on the Soret coefficient. Compared to the experimental data, the simulation results show the same trend. With increasing degree of branching, the Soret coefficient becomes larger. The negative Soret coefficient of the hydrocarbon chains indicates the enrichment in the warm side. We were able to find an empirical correlation between the properties of the pure components and the Soret coeffcients of the considered mixtures.
我们通过实验和反向非平衡分子动力学研究了烃链等摩尔混合物在环己烷、对二甲苯和邻二甲苯中的热扩散行为。为了保持质量贡献并研究形状对索雷特系数的影响，我们考虑了具有相同碳原子数的庚烷、2,3 - 二甲基戊烷、2,4 - 二甲基戊烷、2 - 乙基 - 3 - 甲基丁二烯和2,4 - 二甲基 - 1,3 - 戊二烯等烃链。与实验数据相比，模拟结果显示出相同的趋势。随着支化度的增加，索雷特系数变大。烃链的负索雷特系数表明在热侧富集。我们能够找到纯组分性质与所考虑混合物的索雷特系数之间的经验关联。
