纳米体系的计算表征

纳米系统在许多应用中发挥着重要作用. 由于纳米体系的复杂性，准确表征其结构和性质很具挑战性. 一种重要的表征手段是基于第一性原理电子结构计算的理论模拟. 近年来低标度和高精度的电子结构算法得到了极大的发展，特别是，适用于周期性体系的杂化密度泛函计算效率得到了显著的提高. 利用电子结构信息，可以发展模拟算法直接获得可与实验对比的数据. 例如，扫描隧道显微谱现在可以使用先进的算法高效地模拟. 当感兴趣的系统与环境存在强耦合时，例如在近藤效应中，求解级联运动方程被证明是一个非常有效的计算表征方法；此外，激发态动力学的第一性原理模拟近年来进展迅速，其中非绝热分子动力学方法发挥了重要作用. 对于涉及化学反应的纳米系统，例如石墨烯生长体系，往往需要发展多尺度模拟方法来表征其原子细节. 本文综述了纳米系统计算表征算法的一些最新进展，先进的算法和软件对于我们更好地了解纳米世界至关重要.

Computational Characterization of Nanosystems

Nanosystems play an important role in many applications. Due to their complexity, it is challenging to accurately characterize their structure and properties. An important means to reach such a goal is computational simulation, which is grounded on ab initio electronic structure calculations. Low scaling and accurate electronic-structure algorithms have been developed in recent years. Especially, the efficiency of hybrid density functional calculations for periodic systems has been significantly improved. With electronic structure information, simulation methods can be developed to directly obtain experimentally comparable data. For example, scanning tunneling microscopy images can be effectively simulated with advanced algorithms. When the system we are interested in is strongly coupled to environment, such as the Kondo effect, solving the hierarchical equations of motion turns out to be an effective way of computational characterization. Furthermore, the first principles simulation on the excited state dynamics rapidly emerges in recent years, and nonadiabatic molecular dynamics method plays an important role. For nanosystem involved chemical processes, such as graphene growth, multiscale simulation methods should be developed to characterize their atomic details. In this review, we review some recent progresses in methodology development for computational characterization of nanosystems. Advanced algorithms and software are essential for us to better understand of the nanoworld.