Revealing the Structure and Noncovalent Interactions of Isolated Molecules by Laser-Desorption/Ionization-Loss Stimulated Raman Spectroscopy and Quantum Calculations
Revealing the Structure and Noncovalent Interactions of Isolated Molecules by Laser-Desorption/Ionization-Loss Stimulated Raman Spectroscopy and Quantum Calculations
复制标题
通过激光解吸/电离损失受激拉曼光谱和量子计算揭示孤立分子的结构和非共价相互作用
DOI：
10.1021/acs.jpclett.1c03336
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发表时间：
2021
期刊：
影响因子：
--
通讯作者：
Bar, Ilana
中科院分区：
文献类型：
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作者：
Shachar, Afik;Kallos, Itai;de Vries, Mattanjah S.;Bar, Ilana
分离分子的结构和动力学特性是必不可少的，但获得这些信息是困难的。我们演示了激光解吸射流冷却/电离损失刺激拉曼光谱，以获得气相中非挥发性分子的拉曼光谱特征。比较了一种测试物质（最丰富的色胺构象）的振动特征，发现它们与密度泛函理论计算得到的比例谐波拉曼谱的振动特征相匹配。振动特征用于识别最突出的高变换器并评估其预测的电子结构。这些发现与非共价相互作用（NCI）分析一起，为电子密度和降低密度梯度提供了新的见解，评估了氢键（N-H··π和C-H··H-C）以及影响结构的吸引和排斥NCI之间的相互作用。这种方法通过桌面激光器在均匀分辨率和宽频率范围内获得孤立的非挥发性分子的振动特征，有望为未来的研究带来巨大的好处。
The structural and dynamical characteristics of isolated molecules are essential, yet obtaining this information is difficult. We demonstrate laser-desorption jet-cooling/ionization-loss stimulated Raman spectroscopy to obtain Raman spectral signatures of nonvolatile molecules in the gas phase. The vibrational features of a test substance, the most abundant conformer of tryptamine, are compared and found to match those resulting from the scaled harmonic Raman spectrum obtained by density functional theory calculations. The vibrational signatures serve to identify the most prominentgaucheconformer and evaluate its predicted electronic structure. These findings, together with noncovalent interaction (NCI) analysis, provide new insights into electron densities and reduced density gradients, assessing the hydrogen bonds (N–H···π and C–H···H–C) and interplay between attractive and repulsive NCIs affecting the structure. This approach accesses vibrational signatures of isolated nonvolatile molecules by tabletop lasers at uniform resolution and in a broad frequency range, promising great benefit to future studies.