Požar Martina, Lovrinčević Bernarda
University of Split, Faculty of Science, Ru era Boškovića 33, 21000 Split, Croatia.
Soft Matter. 2024 Oct 16;20(40):8061-8067. doi: 10.1039/d4sm00741g.
Aqueous glycerol mixtures are investigated over the whole concentration range of glycerol = 0.1-0.9 molecular dynamics (MD) simulations at ambient pressure and temperature. Two glycerol force fields are used: an all-atom (AA) and a united-atom (UA) model. Structural changes upon different mixing ratios are discussed through the site-site radial distribution functions (RDFs), coordination numbers and cluster analysis. As both species are hydrogen bonded, they form an almost perfect H-bonded network, with no observed clusters. There are, however, noticeable changes in the RDFs. Glycerol correlations grow stronger with increasing glycerol content, as do water correlations. There is significant transformation in dynamics as well, as evidenced by the self-diffusion coefficients, the velocity autocorrelation functions and the rotational autocorrelation functions. Diffusion of both species slows down with increasing glycerol content. Rotational relaxation is also altered depending on the mixture composition and there is a slow-down at the lower end of glycerol content.
在环境压力和温度下，通过分子动力学（MD）模拟研究了甘油浓度在0.1 - 0.9整个范围内的甘油水溶液混合物。使用了两种甘油力场：全原子（AA）模型和联合原子（UA）模型。通过位点 - 位点径向分布函数（RDF）、配位数和聚类分析讨论了不同混合比例下的结构变化。由于两种物质都能形成氢键，它们形成了一个几乎完美的氢键网络，未观察到聚集体。然而，RDF有明显变化。随着甘油含量的增加，甘油相关性增强，水的相关性也是如此。动力学也有显著转变，这由自扩散系数、速度自相关函数和旋转自相关函数证明。两种物质的扩散都随着甘油含量的增加而减慢。旋转弛豫也根据混合物组成而改变，并且在甘油含量较低时会减慢。
