采用分子轨道从头算方法,分别在HF、MP2和B3LYP水平下对三种全氟烷基碘化物分子CF3I、C2F5I和n-C3F7I的振动红外光谱和喇曼光谱进行理论计算,给出了各频率所对应的振动模式对称性、红外谱线相对强度及喇曼活性.结合计算值和实验值对三种全氟烷基碘化物分子的振动光谱进行了讨论,结果表明理论计算值与实验观测值吻合得很好.

The vibrational infrared spectra and Raman spectra of three perfluoroalkyl iodides(CF3I、C2F5I and n-C3F7I) were calculated by using ab initio molecular orbital theory at the HF、MP2 and B3LYP levels. To every frequency,the symmetries of vibrational modes,relative intensities of infrared spectra and Raman activities were given.Comparisons between calculated and experimental spectra of the three perfluoroalkyl iodides were made and the result showed that theoretical calculation was in good agreement with experimental values.