Ghosh Ayanjeet, Remorino Amanda, Tucker Matthew J, Hochstrasser Robin M
Department of Chemistry, University of Pennsylvania, Philadelphia, PA 19104-6323, USA.
Chem Phys Lett. 2009 Feb 17;469(4-6):325-330. doi: 10.1016/j.cplett.2008.12.094.
The CN vibrations of two aromatic nitriles, cinnamonitrile, PhCH=CH-CN and benzonitrile, PhCN, representative of components of common enzyme inhibitors, are examined by two dimensional infrared spectroscopy. In methanol, these spectra display cross peaks between the two CN components whose evolution exposes the few picosecond (4.5 ps for CIN and 5.3 ps for BN) equilibrium dynamics of hydrogen bond making and breaking. The main features of the 2D IR spectra are reproduced by simulations only with exchange incorporated. The lowest free energy state is the non-hydrogen bonded form. Both alkyl and aryl nitriles have now shown this picosecond exchange process.
通过二维红外光谱对两种芳香腈（肉桂腈，PhCH=CH-CN和苯甲腈，PhCN，常见酶抑制剂的代表性成分）的碳氮（CN）振动进行了研究。在甲醇中，这些光谱显示了两种CN成分之间的交叉峰，其演化揭示了氢键形成和断裂的几皮秒（肉桂腈为4.5皮秒，苯甲腈为5.3皮秒）的平衡动力学。二维红外光谱的主要特征仅通过包含交换的模拟得以重现。最低自由能状态是非氢键结合形式。现在烷基腈和芳基腈均已显示出这种皮秒交换过程。
