Abstract Stable organic radicals serve as model systems for investigating metal-free magnetic phenomena at (sub)nanometer length scales. We have investigated at the single-molecule level the stable π-radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) adsorbed at the elbow sites of the 22 × 3 reconstructed Au(111) surface. Low-temperature scanning tunneling microscopy (STM) and -spectroscopy under ultrahigh vacuum conditions at 8 K reveal structural as well as frontier-orbital related electronic details of DPPH/Au(111). A Kondo-like spectroscopic signature indicates preservation of the unpaired electron spin state.

中文翻译：

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稳定的 π-自由基 2,2-二苯基-1-苦基肼 (DPPH) 吸附在 22×3 重构 Au(111) 的肘部

摘要 稳定的有机自由基可作为研究（亚）纳米长度尺度的无金属磁现象的模型系统。我们在单分子水平上研究了稳定的 π-自由基 2,2-二苯基-1-苦基肼 (DPPH) 吸附在 22 × 3 重建 Au(111) 表面的肘部位置。低温扫描隧道显微镜 (STM) 和 8 K 超高真空条件下的 β 光谱揭示了 DPPH/Au(111) 的结构和前沿轨道相关电子细节。类似 Kondo 的光谱特征表明未配对电子自旋状态的保留。