中文摘要：

在B3LYP/6-311＋G^＊＊水平上对胞嘧啶…CO复合物体系进行了理论计算,发现了6个能量极小的复合物.其结合方式是CO的C或O原子与胞嘧啶的N—H键形成氢键,最稳定的复合物的结合能为-8.72kJ·mol^-1.CO的C原子与胞嘧啶的结合具有更强的优势,C原子结合的复合物中CO的键长缩短,而O结合的复合物中CO键长伸长.同时,对复合物的振动分析发现,在C原子结合的复合物中CO的伸缩频率蓝移,而O结合的复合物中CO伸缩频率是红移的.

英文摘要：

The calculations on the interaction between cytosine and carbon monoxide have been performed at B3LYP/6-311＋G ^＊ ＊ level and six local minimum isomers have been found. Both C and O can combine with N-H bond of cytosine and then hydrogen bonds between them are formed. The carbon atom of CO has a privilege to bind with cytosine. The length of CO bond is diminished in C combined complexes and it is lengthened in O combined complexes. In addition, the frequencies of CO suffer blue shifts in the former and red shifts in the latter.