Guizhou Provincial Key Laboratory of Computational Nano-Material Science, Guizhou Education University, Guiyang 550018, China.
J Chem Phys. 2017 May 21;146(19):194705. doi: 10.1063/1.4983697.
We report the effects of an electric field E on the spin orientations of nickelocene (Nc) deposited on the Cu surfaces by means of first-principles calculations. We employ the Hubbard-U corrected van der Waals density functional to take into account the strong correlation effects of the localized 3d electrons and the non-covalent binding involved in the molecule-surface coupling. We show that the deposited Nc molecule can switch between in-plane (in small E-field) and perpendicular magnetization (in large E-field). We find that the significant charge transfer between the molecule and the metallic surface plays a dominant role in the spin reorientation transition. From an electronic structure perspective, the shift in the Fermi level enhances the coupling between the occupied and unoccupied Ni-3d states of different spin states, which tends to facilitate the perpendicular magnetic anisotropy. These findings shed some light on the electrical control of the magnetic anisotropies of single-molecule magnets on metal surfaces.
我们通过第一性原理计算报告了电场 E 对沉积在 Cu 表面上的二茂镍（Nc）自旋取向的影响。我们采用了 Hubbard-U 修正的范德华密度泛函来考虑局域 3d 电子的强关联效应和分子-表面耦合中涉及的非共价键合。我们表明，沉积的 Nc 分子可以在面内（在小电场中）和垂直磁化（在大电场中）之间切换。我们发现，分子和金属表面之间的显著电荷转移在自旋重定向跃迁中起着主导作用。从电子结构的角度来看，费米能级的移动增强了不同自旋态的占据和未占据 Ni-3d 态之间的耦合，这有助于促进垂直磁各向异性。这些发现为在金属表面上单分子磁体的磁各向异性的电控制提供了一些启示。
