X—H…Y(Y为电子供体)型氢键形成时,X-H键长伸长或缩短与相应的X-H伸缩振动频率红移或蓝移存在较强的相关性,这也是氢键光谱检测和研究的基础.但是,最近的理论研究却推翻了这一观点,认为X-H键长变化和相应的X-H伸缩振动频率移动在有些氢键体系中并不存在相关性(McDowell,S.A.C.;Buckingham,A.D.J.Am.Chem.Soc.2005,127,15515.).本文中,我们采用更为可信的计算方法,对这一问题进行再研究.结果表明是错误的计算方法导致了McDowell和Buckingham得出错误的结论.在McDowell和Buckingham所研究的氢键体系中,X-H键长变化和相应的X-H伸缩振动频率移动仍存在较强的相关性.%The correlation between the X-H bond-length change and the corresponding X-H stretching frequency shift upon X - H … Y (Y is an electron donor) hydrogen bond formation is the basis for the spectroscopic detection and investigation of the hydrogen bond.However,this view has been questioned in a recent report,suggesting that the widely accepted correlation between the bond-length change and the frequency shift in hydrogen-bonded complexes is unreliable (McDowell,S.A.C.; Buckingham,A.D.J.Am.Chem.Soc.2005,127,15515.).In this work,several robust computational methods have been used to investigate this issue.The results clearly show that a computational artifact leads to the conclusion incorrectly reported by McDowell and Buckingham and that the correlation between the X- H bond-length change and the corresponding X- H stretching frequency shift is still very good in the hydrogen-bonded complexes studied.
展开▼
