Diffusion coefficients of elemental compounds in various atmospheres

在自组装体系中，溶质和溶剂分子之间的相互作用对元素分子的扩散有很大影响。为了研究普通有机化合物和具有配位键的金属有机络合物等溶质在液态有机溶剂、液态水、超临界二氧化碳和二氧化碳膨胀甲醇中的相互作用对溶质扩散系数的影响，用瞬变响应技术、泰勒色散和层析脉冲响应法测定了二氧化碳和甲醇混合物的扩散系数。结果表明，扩散系数的大小主要受分子尺寸的影响，其次受相互作用的影响。在从超临界流体、气体膨胀液体到液体的范围内，扩散系数与溶剂粘度大致相关。

In self-assembly systems diffusion of elemental molecules is significantly affected by interactions between solute and solvent molecules. To study the interaction on solute diffusion coefficients, diffusion coefficients of various solutes such as ordinary organic compounds and organometallic complexes having coordination bondings in liquid organic solvent, liquid water, supercritical carbon dioxide and carbon dioxide expanded methanol, a mixture of carbon dioxide and methanol were measured by the transient response techniques, the Taylor dispersion and chromatographic impulse response method. As a result, the values of diffusion coefficients were mainly dominated by the molecular size, and secondarily affected by the interaction. The diffusion coefficients were roughly correlated by the solvent viscosities over the range from supercritical fluid, gas expanded liquid to liquid states.