论文标题
非磁性分子的电子自旋共振扫描隧道显微镜
Electron Spin Resonance Scanning Tunneling Microscope of Non-Magnetic Molecules
论文作者
论文摘要
石墨烯上C60自由基离子的电子自旋共振隧穿显微镜（ESR-STM）是自由基的首次演示。根据富勒烯自由基离子的宏观ESR测量G = 2.00处的ESR-STM信号。 ESR-STM信号取决于偏置电压，因为它反映了分子的电荷状态。该信号出现在偏置电压中，该电压能够使最低的无置分子轨道（Lumo）（产生自由基阴离子）和最高占用的分子轨道（HOMO（产生）C60分子的分子轨道（产生）时，它是C60分子的。 线宽提供有关自由基寿命的信息。在几个实验中，观察到13C超精细分裂，并且ESR-STM峰的相变为磁场扫描速度的函数。这可能用于提供有关分子松弛时间的信息。同时，将G = 1.6处的ESR-STM信号归因于尖端顶点处的氧化钨（W5+），这不是偏置电压依赖性的。 ESR-STM探索非顺磁分子的能力，显着扩大了该技术的范围。
Electron Spin Resonance-Scanning Tunneling Microscopy (ESR-STM) of C60 radical ion on graphene is a first demonstration on radical ions. ESR-STM signal at g=2.00 was measured in accordance with macroscopic ESR of fullerene radical ion. The ESR-STM signal was bias voltage dependent, as it reflects the charge state of the molecule. The signal appears in the bias voltage which enables the ionization of the lowest unoccupied molecular orbital (LUMO) (creation of radical anion) and the highest occupied molecular orbital (HOMO (creation of a radical cation) of the C60 molecule when it deposited on graphene. The linewidth provides information on the lifetime of the free radical. In several experiments, a 13C hyperfine splitting was observed, and a change in the phase of the ESR-STM peak as a function of the speed of the magnetic field sweep was changed. This might be used to provide information on the relaxation times of the molecules. In parallel, ESR-STM signal at g=1.6 was ascribed to Tungsten oxide (W5+) at the tip apex, which is not bias voltage dependent. The ability of ESR-STM to explore non paramagnetic molecules, significantly broadens the scope of this technique.
