Beijing National Laboratory for Molecular Sciences, Key Laboratory for the Physics and Chemistry of Nanodevices, State Key Laboratory of Rare Earth Materials Chemistry and Applications, College of Chemistry and Molecular Engineering, Peking University , Beijing 100871, China.
ACS Nano. 2016 Dec 27;10(12):10789-10797. doi: 10.1021/acsnano.6b04453. Epub 2016 Nov 29.
In this work, we report an accurate and convenient method that can be used to assign the chirality of all metallic single-walled carbon nanotubes (M-SWNTs). This method is designed based on the electronic Raman scattering (ERS) features, which are resonantly enhanced at the corresponding excitonic transition energies (M and M). Using this method, we are able to accurately determine the electronic property M with the resolution of a vibrational Raman spectroscopy (∼0.3 meV), which is significantly higher than that of the electronic spectroscopies (∼3 meV). We use the M splitting value, which is found insensitive to environmental changes, as a universal criteria for (n,m) assignments in various environments. As an illustrative example, simply using a commercialized Raman spectrometer with two laser lines (1.959 and 2.330 eV), we are able to unambiguously assign 18 metallic chiralities with M in the 1.6-2.3 eV range in our samples. This method provides an accurate database of M's in a similar way as photoluminescence excitation spectroscopy does for S's. It can facilitate further systematic studies on the properties of M-SWNTs with defined chirality.
在这项工作中，我们报告了一种准确且方便的方法，可用于分配所有金属单壁碳纳米管（M-SWNTs）的手性。该方法基于电子拉曼散射（ERS）特征设计，在相应的激子跃迁能量（M 和 M）处得到共振增强。使用这种方法，我们能够以振动拉曼光谱学的分辨率（约 0.3 meV）准确确定电子性质 M，这明显高于电子光谱学的分辨率（约 3 meV）。我们使用 M 分裂值作为（n，m）在各种环境中的分配的通用标准，发现其对环境变化不敏感。作为一个说明性的例子，仅使用具有两个激光线（1.959 和 2.330 eV）的商业化拉曼光谱仪，我们能够在我们的样品中明确地分配 M 在 1.6-2.3 eV 范围内的 18 种金属手性。这种方法以类似于光致发光激发光谱对 S 的方式提供了 M 的准确数据库。它可以促进进一步对具有定义手性的 M-SWNTs 性质的系统研究。
