从头计算研究CH_3C(O)OSSOC(O)CH_3的构型和能量  

Ab initio study on CH_3C(O)OSSOC(O)CH_3:configurations and energies

作　　者：王克栋[1] 关君[2] 朱川川[1] 刘玉芳[1] 

机构地区：[1]河南师范大学物理与信息工程学院,新乡453007 [2]新乡广播电视大学继续教育学院,新乡453003

出　　处：《物理学报》2011年第7期212-217,共6页Acta Physica Sinica

基　　金：河南省自然科学基金(批准号:082300410030);河南师范大学博士科研启动基金(批准号:525449)资助的课题~~

摘　　要：采用从头计算B3LYP,MP3和MP4方法结合Aug-cc-pVDZ基组研究了CH3C(O)OSSOC(O)CH3最稳定的五种构象及其阳离子构型.理论计算了五种稳定构象的转动常数和偶极矩;运用电子传播子理论P3近似方法计算稳定构象外价壳层轨道的电离能,计算结果与光电子能谱实验结果符合的较好.根据构象的相对能量以及理论模拟电离能谱和实验光电子能谱之间的比较,说明在气相光电子能谱实验中至少存在两种构象.与中性构型相比,电离后的五种阳离子构型均发生了明显的结构弛豫,尤其是发现二面角C2O4S5S10和O4S5S10O9发生较大的转动.The five low-lying configurations of CH3C （O）OSSOC （O）CH3 are studied by ab initio calculations by B3LYP, MP3 and MP4 methods with Aug-cc-pVDZ basis set. Their rotational constants and dipole moments of these five configurations are determined. The vertical ionization energies of the configurations, calculated with electron propagator theory in the P3/ 6-311 ＋ ＋ G（2d,2p） approximation, are in agreement with the experimental data from photoelectron spectroscopy. The relative energies of the configurations and the comparison between the simulated and the experimental photoelectron spectra demonstrate that there are at least two configurations of CH3C （O）OSSOC （O）CH3 in the gas-phase experiments. The geometrical parameters of five lowest-lying configurations are optimized in the cationic state and compared with those of the neutral configuration. Remarkable structural relaxations after ionization are found, especially for the dihedral angles D （C2O4S5S10） and D（O4S5S10O9）.

关 键 词：构象 电离能 相对能量 光电子能谱 

分 类 号：O561.1[理学—原子与分子物理]