论文标题
氟化Fe（1,10-phenantroline）的反旋转跨界
Inverse spin crossover in fluorinated Fe(1,10-phenanthroline)$_2$(NCS)$_2$ adsorbed on Cu (001) surface
论文作者
论文摘要
Density functional theory (DFT) including van der Waals weak interaction in conjunction with the so called rotational invariant DFT+U, where $U$ is the Hubbard interaction of the iron site, is used to show that the fluorinated spin crossover Fe(phen$)_{2}$(NCS$)_{2}$ molecule whether in the gas phase or adsorbed on Cu(001) surface switches from the原始低旋转状态至高旋转状态。使用BadER电子密度分析，用fe-octahedron笼子的电子掺杂来解释自旋交叉的这种反转，从而导致Fe-N键长的增加。因此，配体场分裂大大降低，使高旋转状态比低旋转状态更稳定。 Tersoff-Hamann近似中计算出的扫描隧道显微镜（STM）图像显示氟化和未氟化的分子之间存在明显的区别。这种理论预测正在等待未来的STM实验确认。
Density functional theory (DFT) including van der Waals weak interaction in conjunction with the so called rotational invariant DFT+U, where $U$ is the Hubbard interaction of the iron site, is used to show that the fluorinated spin crossover Fe(phen$)_{2}$(NCS$)_{2}$ molecule whether in the gas phase or adsorbed on Cu(001) surface switches from the original low spin state to the high spin state. Using Bader electron density analysis, this inversion of the spin-crossover is explained in terms of electron doping of the Fe-octahedron cage which led to an increase of the Fe-N bond lengths. Consequently, the ligand-field splitting is drastically reduced, making the high-spin ground state more stable than the low-spin state. The calculated scanning tunneling microscopy (STM) images in the Tersoff-Hamann approximation show a clear distinction between the fluorinated and the unfluorinated molecule. This theoretical prediction is awaiting future STM experimental confirmation.
