Molecular dynamics simulation of the aggregation phenomenon in the late stages of silica materials preparation
Molecular dynamics simulation of the aggregation phenomenon in the late stages of silica materials preparation
复制标题
DOI：
10.1016/j.ces.2018.03.045
复制
发表时间：
2018-07-20
影响因子：
4.7
通讯作者：
Wang, Yujun
中科院分区：
文献类型：
--
作者：
Gholizadeh, Reza;Wang, Yujun
采用分子动力学模拟研究了胶体溶液中二氧化硅生产后期的聚集行为，以发现对所产生的聚集体和孔的结构和动力学的新见解。所实现的理论研究使用非晶细胞和Forcite模块，和材料工作室包Dreiding力场。计算了关键热力学参数、均方位移和径向分布函数。结果表明，由于吉布斯自由能为负值，聚集发生在后期。生成的“团聚体和孔隙”的直径不断增加，而“团聚体和孔隙”的数量先增加后减少。随着反应的进行，孔体积先增大后减小。反应物数目的变化对孔和聚集体的拓扑结构有明显的影响。当更有效的分子参与聚集过程时，聚集体和孔的数量有增加的趋势，而它们的直径略有减小。此外，对聚集体的形状进行了检查，发现聚集体的主要形状为球形。(C)2018爱思唯尔有限公司版权所有
Molecular dynamics simulations are employed to investigate the aggregation behavior at the late stages of silica production in a colloidal solution to find new insights into the structures and dynamics of the produced aggregates and pores. The implemented theoretical investigations used the Amorphous cell and Forcite modules, and Dreiding force field of Materials Studio package. The key thermodynamic parameters, mean squared displacements, and radial distribution functions were calculated. Results revealed that aggregation occurred in the late stages due to the negative value of Gibbs free energy. Diameters of the generated "aggregates and pores" continuously increased while the number of "aggregates and pores" first increased and then decreased. Furthermore, the volume of pores first rose and then fell as the reaction proceeded. Variations of reactant numbers had the noticeable influence on the pores and aggregates topologies. The number of aggregates and pores had an upward trend while their diameters slightly reduced when more effective molecules were involved in the aggregation process. In addition, the shape of the aggregates examined and found that the predominant shapes of the aggregates were spherical. (C) 2018 Elsevier Ltd. All rights reserved.