Anharmonic vibrations of nucleobases: Structural basis of one-and two-dimensional infrared spectra for canonical and mismatched base pairs  

作　　者：WANG GuiXiu ZHAO Juan WANG JianPing 

机构地区：[1]Beijing National Laboratory for Molecular Sciences,State Key Laboratory of Molecular Reaction Dynamics,Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China

出　　处：《Science China Chemistry》2011年第10期1590-1606,共17页中国科学(化学英文版)

基　　金：supported by the National Natural Science Foundation of China (20727001 and 30870591);the National Basic Research Program of China (973, 2007CB815205);the Chinese Academy of Sciences through the Hundred Talent Fund

摘　　要：Canonical Watson-Crick base pairs and four representative mismatched base pairs have been studied by quantum chemical computations. Detailed anharmonic vibrational analysis was carried out to reveal some vibrational signatures characteristic of structural aspects of the base monomers and dimers, which were well manifested in simulated 1D IR and 2D IR spectra. The degree of delocalization of the selected normal modes, represented by the potential energy distribution, was found to vary sig-nificantly from isolated bases to H-bonded dimers, and was accompanied by changes in anharmonicities of these modes. Examples are given for the generally accepted carbonyl stretching mode of base pairs appearing in the 6-m wavelength region of IR spectra.Canonical Watson–Crick base pairs and four representative mismatched base pairs have been studied by quantum chemical computations. Detailed anharmonic vibrational analysis was carried out to reveal some vibrational signatures characteristic of structural aspects of the base monomers and dimers, which were well manifested in simulated 1D IR and 2D IR spectra. The degree of delocalization of the selected normal modes, represented by the potential energy distribution, was found to vary sig-nificantly from isolated bases to H-bonded dimers, and was accompanied by changes in anharmonicities of these modes. Examples are given for the generally accepted carbonyl stretching mode of base pairs appearing in the 6-m wavelength region of IR spectra.

关 键 词：quantum chemical computation canonical Watson–Crick base pair mismatched base pair anharmonic vibration infrared 

分 类 号：O621.2[理学—有机化学]