论文标题
扭曲石墨烯的密度功能研究$ L1_0 $ -FEPD异质界面
Density functional study of twisted graphene $L1_0$-FePd heterogeneous interface
论文作者
论文摘要
近年来已经对$ L1_0 $ -FEPD（001）进行的$ L1_0 $ -FEPD（001）的石墨烯是一种异质界面，是一个异质的界面，在石墨烯和四方合金表面的蜂窝结构之间具有显着的晶格对称性不匹配。在这项工作中，我们报告了其原子尺度构型，电子和磁性以及吸附机制的密度功能研究，这些功能在先前的实验研究中尚未得到充分了解。我们提出了各种原子尺度模型，包括简单的非旋转和低压扭曲接口，并通过使用DFT-D2和OPTB86B-VDW函数的Van der Waals相互作用进行结构优化来分析其能量稳定性。最稳定结构的结合能达到$ e_ \ mathrm {b} = -0.22 $ 〜ev/dft-d2（$ e_ \ mathrm {b} = -0.19 $ 〜ev/atom for optb86b-vdw）。计算出的FEPD-GRAPHENE间距距离约为2 〜Å，成功再现了实验值。我们还发现了特征性的行为：$π$ - 带的调制，抑制吸附能的位点依赖性以及\ color {blue}moirélike\ color {black volor {black} ill corruged屈曲。此外，我们的原子结构有望帮助构建低成本计算模型，以研究$ L1_0 $合金/二维接口的物理特性。
Graphene on $L1_0$-FePd(001), which has been experimentally studied in recent years, is a heterogeneous interface with a significant lattice symmetry mismatch between the honeycomb structure of graphene and tetragonal alloy surface. In this work, we report on the density functional study of its atomic-scale configurations, electronic and magnetic properties, and adsorption mechanism, which have not been well understood in previous experimental studies. We propose various atomic-scale models, including simple nontwisted and low-strain twisted interfaces, and analyze their energetical stability by performing structural optimizations using the van der Waals interactions of both DFT-D2 and optB86b-vdW functionals. The binding energy of the most stable structure reached $E_\mathrm{B}=-0.22$~eV/atom for DFT-D2 ($E_\mathrm{B}=-0.19$~eV/atom for optB86b-vdW). The calculated FePd-graphene spacing distance was approximately 2~Å, which successfully reproduced the experimental value. We also find out characteristic behaviors: the modulation of $π$-bands, the suppression of the site-dependence of adsorption energy, and the rise of \color{blue} moiré-like \color{black} corrugated buckling. In addition, our atomic structure is expected to help build low-cost computational models for investigating the physical properties of $L1_0$ alloys/two-dimensional interfaces.
