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采用密度泛函B3LYP(Becke,three-parameter,Lee-Yang-Parr)/6-311++G**和HF(HartreeFock)/6-311++G**方法,从理论上探讨了2-F-四氢呋喃(2-F-Tetrahydrofuran)分别与几种常见而重要的生物小分子咪唑(Iminazole)、嘧啶(Pyrimidine)、腺嘌呤(Adenine)和鸟嘌呤(Guanine)等分子间的弱相互作用,发现分子间同时存在N…H常规氢键和C-F…H-C赝氢键结构.弱相互作用能计算表明4个复合物的相对稳定性顺序为:Guanine…F>Iminazole…F>Adenine…F>Pyrimidine…F.通过对C-F…H-C赝氢键几何结构、振动频率、自然键轨道和电子密度拓扑性质的理论计算,总结了C-F…H-C赝氢键不同于常规氢键的4个特征.当分子中的F官能团作为电子供体与另一分子中的H-C-基团(电子受体)相互作用时,F会活化C-H,从而形成分子间或基团间的弱相互作用——C-F…H-C赝氢键.
By using B3LYP (Becke, three-parameter, Lee-Yang-Parr) / 6-311 ++ G ** and HartreeFock / 6-311 ++ G ** methods, F-Tetrahydrofuran (2-F-Tetrahydrofuran) and several common and important biological small molecules such as imidazole, pyrimidine, adenine and guanine, The results show that there exist N · H regular hydrogen bonds and CF ... HC pseudo hydrogen bonds between molecules simultaneously. Weak interaction energy calculations show that the relative stability of the four complexes is: Guanine ... F> Iminazole ... F> Adenine ... F> Pyrimidine ... F. By summarizing the topological properties of CF ... HC pseudo-hydrogen bond geometry, vibrational frequencies, natural bond orbital and electron density, four characteristics of CF ... HC pseudo-hydrogen bonds different from conventional hydrogen bonds are summarized. Of the F functional group as an electron donor interacts with an HC-group (electron acceptor) in another molecule, F activates CH to form intermolecular or intermolecular weak interactions - CF ... HC pseudo-hydrogen bonding .