Stania R, Seitsonen A P, Kunhardt D, Büchner B, Popov A A, Muntwiler M, Greber T
Physik-Institut , Universität Zürich , CH-8057 Zürich , Switzerland.
Département de Chimie , École Normale Supérieure , F-75005 Paris , France.
J Phys Chem Lett. 2018 Jul 5;9(13):3586-3590. doi: 10.1021/acs.jpclett.8b01326. Epub 2018 Jun 18.
Ions inside of fullerene molecules are model systems for the study of the electrostatic interaction across a single layer of carbon. For TbScN@C on h-BN/Ni(111), we observe with high-resolution X-ray photoelectron spectroscopy a splitting of the C 1s core level. The data may be explained quantitatively with density functional theory. The correlation of the C 1s eigenvalues and the Coulomb potential of the inside ions at the corresponding carbon sites indicates incomplete screening of the electric field due to the endohedral ions. The screening comprises anisotropic charge transfer to the carbon atoms and their polarization. This behavior is essential for the ordering of endohedral single-molecule magnets and is expected to occur in any single-layer material.
富勒烯分子内部的离子是用于研究跨单层碳的静电相互作用的模型系统。对于在h-BN/Ni(111)上的TbScN@C，我们用高分辨率X射线光电子能谱观察到C 1s核心能级的分裂。这些数据可以用密度泛函理论进行定量解释。C 1s本征值与相应碳位点处内部离子的库仑势之间的相关性表明，由于内包离子，电场的屏蔽不完全。这种屏蔽包括向碳原子的各向异性电荷转移及其极化。这种行为对于内包单分子磁体的有序排列至关重要，并且预计会在任何单层材料中出现。
