AuCo nanoparticles: ordering, magnetisation, and morphology trends predicted by DFT - data

Magnetism achieved at the nano-level has been successfully employed in many diverse applications ranging from catalysis, over magnetic data storage, to recently discovered novel biomedical MRI and hyperthermia approaches. In this quest, nanoparticles combining highly magnetic cobalt and inert gold offer many application-specific advantages, such as strong magnetic anisotropy, where the relationship between the nanoparticle morphology and its magnetic properties plays a crucial role. It is therefore important to establish connection between the size, shape, and atomic arrangement of metallic species, and the resulting magnetic performance. The morphology-induced changes in magnetisation of AuCo nanoparticles have been predicted by density functional theory (DFT) calculations for sizes between 0.5 and 2.0 nm in diameter in three shapes (icosahedron, decahedron, cuboctahedron) and distinct chemical orderings (core-shell, L10 ordered, disordered). Data is collected in one .xslx file and it includes structural, magnetic, and electronic properties of modelled nanoparticles. The first sheet contains optimised geometries for core-shell AuCo nanoparticles of varying shapes and sizes, atom-resolved spin magnetic moments, orbital magnetic moments for both easy and hard magnetisation axis, and total energies of the system when relaxed under the influence of differently aligned magnetic fields given in the lattice plane vectors (e.g. 001 and 100 for icosahedron). The second sheet contains the same information for L10 ordered AuCo nanoparticles, whereas atom-resolved charges of all atomic arrangements are given in the third sheet. Structural information is given in the form of a universal scaling factor followed by lattice vectors (in Angstrom), constituent elements, number of atoms, and atomic coordinates directly related to the sizes of cell vectors. Charges are listed for each atom as multiples of the elementary charge unit (|e|). Atom-decomposed magnetic moments in Bohr magnetons (μB) as obtained through the DFT calculations were separated in spin and orbital moments for each of the s, p, and d electron shells. Finally, magnetic anisotropy was calculated as a difference between the energies of two distinct magnetisation directions through non-collinear spin-polarised DFT calculations, and obtained energies in eV for each of the magnetisation axes are given for all of the studied systems. All untis have been listed alongside the name of the physical property.
Data has been generated through density functional theory calculations as implemented in Vienna Ab Initio Simulation Package (VASP), and is hence given in the data set in the form as provided by the software's input and output files.
Research results based upon these data are published at http://doi.org/10.1039/d2cp00648k

纳米级磁性已成功应用于诸多跨领域场景，涵盖催化、磁数据存储，以及近年新兴的生物医学磁共振成像（Magnetic Resonance Imaging, MRI）与热疗技术。在此研究方向中，兼具高磁性钴与惰性金的纳米颗粒具备诸多适配特定应用的优势，例如优异的磁各向异性；其中纳米颗粒的形貌与其磁性能之间的关联，发挥着至关重要的作用。因此，明确金属纳米颗粒的尺寸、形貌与原子排布，与其最终磁性能之间的关联，具有重要意义。针对直径介于0.5~2.0 nm的AuCo纳米颗粒，本数据集通过密度泛函理论（Density Functional Theory, DFT）计算，预测了其在三种形貌（二十面体、十面体、立方八面体）与三种不同化学有序结构（核壳结构、L10有序结构、无序结构）下，形貌诱导的磁化强度变化。本数据集收纳于单个.xlsx文件中，涵盖建模纳米颗粒的结构、磁学与电子学性质。第一个工作表包含不同形貌与尺寸的核壳型AuCo纳米颗粒的优化几何结构、原子分辨自旋磁矩、易磁化轴与难磁化轴的轨道磁矩，以及系统在不同取向磁场作用下弛豫后的总能量；磁场取向以晶格平面矢量表示（例如二十面体对应的001与100晶面）。第二个工作表包含L10有序型AuCo纳米颗粒的同类信息，而所有原子排布的原子分辨电荷则位于第三个工作表中。结构信息以通用缩放因子、晶格矢量（单位：埃（Å））、组成元素、原子总数，以及与晶胞矢量尺寸直接相关的原子坐标的形式呈现。各原子的电荷以元电荷（|e|）的倍数形式列出。通过DFT计算得到的原子分解磁矩以玻尔磁子（μB）为单位，且针对s、p、d电子壳层分别拆分出自旋磁矩与轨道磁矩。最后，通过非共线自旋极化DFT计算，将磁各向异性定义为两种不同磁化方向的能量差；所有研究体系的各磁化轴对应的能量均以电子伏特（eV）为单位给出。所有物理量的单位均与其名称一同标注。
本数据集的数据通过维也纳从头算模拟包（Vienna Ab Initio Simulation Package, VASP）实现的密度泛函理论计算生成，因此数据格式与该软件的输入、输出文件保持一致。
基于本数据集的研究成果已发表于：http://doi.org/10.1039/d2cp00648k