中文摘要：

为了可控制备分散性的Au纳米粒子，研究Au纳米粒子在溶剂中的界面结构及相互作用。采用分子动力学模拟方法研究不同温度下氟化的硫醇十二烷钝化的Au纳米粒子在超临界CO2中的界面结构和相互作用自由能。结果表明：温度升高会略微提升纯排斥的特征。通过自由能的分解，发现Au纳米内核与吸附的有机配体间的相互作用完全决定了自由能的排斥特征。焓熵分析结果表明自由能的排斥特征是由熵贡献引起的。

英文摘要：

To prepare gold nanoparticles with controllable dispersion feature, the interracial structures and interaction were required in solvent media. The interracial structure and free energy between two 1 H, 1H, 2H, 2H-perfluorododecanethiol-capped gold nanocrystals in supercritical carbon dioxide at different system temperatures was studied through molecular dynamic simulation. The free energy exhibited a slightly increased repulsion feature at higher temperature. The decomposition of the free energy showed that the interaction between the gold core and capping ligands wholly controlled the total profile of the free energy. An entropy-enthalpy analysis was performed and it demonstrated that the repulsive feature of the free energy was driven by the contribution of entropy.