AACSD: An atomistic analyzer for crystal structure and defects

We have developed an efficient command-line program named AACSD (Atomistic Analyzer for Crystal Structure and Defects) for the post-analysis of atomic configurations generated by various atomistic simulation codes. The program has implemented not only the traditional filter methods like the excess potential energy (EPE), the centrosymmetry parameter (CSP), the common neighbor analysis (CNA), the common neighborhood parameter (CNP), the bond angle analysis (BAA), and the neighbor distance analysis (NDA), but also the newly developed ones including the modified centrosymmetry parameter (m-CSP), the orientation imaging map (OIM) and the local crystallographic orientation (LCO). The newly proposed OIM and LCO methods have been extended for all three crystal structures including face centered cubic, body centered cubic and hexagonal close packed. More specially, AACSD can be easily used for the atomistic analysis of metallic nanocomposite with each phase to be analyzed independently, which provides a unique pathway to capture their dynamic evolution of various defects on the fly. In this paper, we provide not only a throughout overview on various theoretical methods and their implementation into AACSD program, but some critical evaluations, specific testing and applications, demonstrating the capability of the program on each functionality.本团队开发了一款高效的命令行程序AACSD（原子晶体结构与缺陷分析仪，Atomistic Analyzer for Crystal Structure and Defects），可用于各类原子模拟程序生成的原子构型的后处理分析。该程序不仅集成了超额势能（Excess Potential Energy, EPE）、中心对称参数（Centrosymmetry Parameter, CSP）、公共近邻分析（Common Neighbor Analysis, CNA）、公共邻域参数（Common Neighborhood Parameter, CNP）、键角分析（Bond Angle Analysis, BAA）以及近邻距离分析（Neighbor Distance Analysis, NDA）等传统结构分析方法，还纳入了多款新近开发的分析手段，包括改进型中心对称参数（Modified Centrosymmetry Parameter, m-CSP）、取向成像图（Orientation Imaging Map, OIM）与局部晶体取向（Local Crystallographic Orientation, LCO）。本次提出的OIM与LCO方法已适配面心立方（Face Centered Cubic, FCC）、体心立方（Body Centered Cubic, BCC）以及密排六方（Hexagonal Close Packed, HCP）三类典型晶体结构。尤为独特的是，AACSD可便捷应用于金属纳米复合材料的原子级分析，且支持对各组分相独立开展分析，这为实时捕获各类缺陷的动态演化过程提供了全新路径。本文不仅全面综述了各类理论分析方法及其在AACSD程序中的实现细节，还提供了关键评测、专属测试与应用案例，以展示该程序各项功能的实际性能。