高壓振動光譜在化學研究上的應用：以生物相關及新興材料分子為例

High-pressure vibrational studies of biological and material molecules

蔡維鉦(Wei-Cheng Tsai) ； 陳冠橋(Guan-Ciao Chen) ； 朱文綺(Wen-Chi Chu) ； 張海舟(Hai-Chou Chang)

《化學》 64卷3期 (2006/09) Pp. 319-334

https://doi.org/10.6623/chem.2006024

摘要

弱作用力的相關研究，近年來蓬勃發展。因應此一趨勢，原有之氫鍵定義，實有修正之必要。C-H---O弱氫鍵訊號因受強氫鍵干擾，導致實驗上很難找到C-H---O存在的證據。目前最新的研究說明壓力增強C-H---O作用力的可能性。因此本文將討論高壓技術在C-H---O弱氫鍵上的應用。本文利用紅外線光譜來研究1,3-dimethylimidazolium methyl sulfate以及1-butyl-3-methylimidazolium hexafluorophosphate這兩種離子溶液在室溫下的氫鍵結構。除此之外，在質子化的thiazole-water系統中，我們使用實驗和計算的方法去分析電荷增加C-H---O作用力的變化。質子化thiazole中aromatic C-H伸縮鍵的低頻率位移證明了弱氫鍵的存在。

關鍵字

高壓 ； 紅外線光譜 ； 拉曼光譜 ； 弱氫鍵

並列摘要

The increased understanding of weak interactions has required an expansion of the classical definition of hydrogen bonding. Evidence of C-H---O hydrogen bonding is difficult to obtain, since C-H---O hydrogen bonds usually coexist with other strong interactions and typically weak. Some studies revealed the potential significance of pressure to control the nature of C-H---O interactions. The pressure-dependence measurements also exhibit considerable spectral changes as the solution is compressed. The hydrogen structures of room temperature ionic liquids, 1,3-dimethylimidazolium methyl sulfate and 1-butyl-3-methylimidazoliumhexfluorophosphate have been studied by infrared spectroscopy. High-pressure infrared spectral profiles and theoretical calculations allow us to make a vibrational assignment of these compounds. Close interactions of the charge-enhanced C-H---O type have been analyzed both experimentally and computationally in the protonated thiazole- water system. The formation of a weak hydrogen bond was directly evidenced by a low-frequency shift of the hydrogen-bonded aromatic C-H stretch in the protonated thiazole moiety.

並列關鍵字

High Pressure ； Infrared Spectrum ； Raman Spectrum ； Weak Hydrogen Bond