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用密度泛函理论（ＤＦＴ）的Ｂ３ＬＹＰ方法（６－３１Ｇ＊基组），计算研究了丁二酰亚胺（ＳＩＭ）的氟、氯和甲基取代物（ＳＩＭＦ，ＳＩＭＣｌ和ＳＩＭＭｅ）的几何构型、电子结构、红外光谱和热力学性质，讨论了取代基效应．结果表明，ＳＩＭＦ和ＳＩＭＣｌ均为平面构型，ＳＩＭＭｅ接近平面构型．羰基伸缩振动频率（νＣ＝Ｏ）均分裂为两个谱带，低频带出现在１７３４～１７７１ｃｍ－１，高频带出现在１７９２～１８２２ｃｍ－１，且前者强于后者．与ＳＩＭ相比，吸电子基（Ｆ和Ｃｌ）使νＣ＝Ｏ和偶极矩增大，推电子基（ＣＨ３）的影响正相反．由校正频率计算了２９８～８００Ｋ温度范围的热力学性质熵（Ｓ°）和热容（Ｃｐ°）．
The geometries of the fluorine, chlorine and methyl substituents (SIMF, SIMCl and SIMMe) of succinimide (SIM) have been calculated using the B3LYP method of density functional theory (DFT) Type, electronic structure, infrared spectra and thermodynamic properties, the effect of substituents was discussed. The results show that both SIMF and SIMCl are planar and SIMMe is near planar. Carbonyl stretching vibration frequency (ν C = O) split into two bands, the low frequency band appears in 1734 ~ 1771cm-1, the high frequency band appears in 1792 ~ 1822cm-1, and the former is stronger than the latter. Compared with SIM, electron-withdrawing groups (F and Cl) increase νC = O and dipole moment, and the effect of electron donating group (CH3) is the opposite. The thermodynamic entropy (S °) and heat capacity (Cp °) of the temperature range of 298 ~ 800K were calculated from the corrected frequency.