Atomic scale modeling of metallic nanoparticles embedded in nanoscale carbon structures

碳纳米管和洋葱提供了一种新的微观测试环境，用于探测单个嵌入式金属纳米颗粒的变形行为，如最近的透射电子显微镜实验所示。辐照诱导的空位的湮灭导致碳纳米结构的半径减小，因此在金属纳米颗粒中诱导机械应力状态，这导致塑性流动。因此，这种方法为研究单个纳米晶体的变形行为铺平了道路，因此提供了有助于理解纳米尺度上变形机制的信息。由于TEM实验提供的信息在给定的时间内的结构的变形状态，但没有发生在短时间尺度上的变形机制的信息，原子尺度的计算机模拟是必要的，以提供补充信息。在这个项目中，我们计划使用原子模拟方法，从动力学蒙特卡罗和分子动力学模拟到基于电子密度泛函理论的计算，研究嵌入由碳网络组成的纳米挤出机中的单个纳米晶体的机械性能。两个纳米系统的组合提供了一个独特的机会来研究单个金属纳米晶体对机械变形的响应。通过与国外合作者的密切联系，包括在这一领域工作的实验和理论小组，我们将能够直接比较理论和实验结果，以发展有关该主题的连贯理论

Carbon nanotubes and onions provide a novel microscopic test environment for probing the deformation behavior of individual embedded metallic nanoparticles as recent experiments by transimission electron microscopy have shown. The annihilation of irradiation induced vacancies leads to a reduction of the radius of the carbon nanostructure and therefore induces mechanical stress states in the metallic nanoparticle that leads to plastic flow. This method therefore paves a way for studying the deformation behavior of individual nanocrytallites and therefore provides information which will help to understand deformation mechanisms on the nanoscale. Since the TEM experiments provide information on the deformed state of the structures at given time, but no information on the deformation mechanisms occuring on short time scales, atomic scale computer simulations are necessary to provide complementary information. Within this project, we plan to study the mechanical properties of individual nanocrystallites embedded in nanoextruders consisting of carbon network using atomistic simulation methods ranging from kinetic Monte Carlo and molecular dynamics simulations to calculations based on electronic density functional theory. The combination of two nanosystems provides a unique opportunity to study the response of individual metal nanocrystallites to mechanical deformation. With a close connection to foreign collaborators, including experimental and theoretical groups working on this field, we will be able to directly compare theoretical and experimental results for developing a coherent theory on the subject