Bis(trifluoroaceto) disulfide (CF3C(O)OSSOC(O)CF3): a HeI photoelectron spectroscopy and theoretical study.
Bis(trifluoroaceto) disulfide (CF3C(O)OSSOC(O)CF3): a HeI photoelectron spectroscopy and theoretical study.
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DOI：
10.1021/jp061050e
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发表时间：
2006-04
期刊：
影响因子：
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通讯作者：
Xiaoqing Zeng;Maofa Ge;Zheng Sun;Dianxun Wang
中科院分区：
文献类型：
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作者：
Xiaoqing Zeng;Maofa Ge;Zheng Sun;Dianxun Wang
合成了双(三氟乙酸基)二硫化物Cf(3)C(O)OSSOC(O)Cf(3)，并用拉曼光谱、光电子能谱和理论计算对其进行了研究。该分子具有双C=O顺式S-S键构象，由于硫-硫孤对相互作用，其结构特征为二面角增量(OSSO)=-95.1度。OSSO的收缩的S-S键(1.979埃)和较高的转动势垒(B3LYP/6-31G水平下的19.29kcal摩尔-1)表明该分子具有部分共振诱导双键的性质。电离后，Cf(3)C(O)OSSOC(O)Cf(3)(*+)的基阳离子自由基构型为跨平面主原子结构(Delta(Osso)=180度，Delta(Ocos)=0度)，具有C(2)(H)对称性。S-S键伸长到2.054埃，而S-O键从中性形式的1.755埃缩短到相应的阳离子-自由基形式的1.684埃。由此得到了9.91 eV的绝热电离能。前两个同位电子对应于主要集中在硫3p孤对MOS上的电子：3ppi{36a(n(A)(S))(-1)和3ppi[35b(n(B)(S)，n(B)(O(C)(=)(O)](-1)，实验能量间隔为0.16 eV。第一垂直电离能为10.81 eV。
Bis(trifluoroaceto) disulfide CF(3)C(O)OSSOC(O)CF(3) was prepared and studied by Raman, photoelectron spectroscopy (PES), and theoretical calculations. This molecule exhibits gauche conformation with both C=O groups cis to the S-S bond; the structure of the OSSO moiety is characterized by dihedral angle delta(OSSO) = -95.1 degrees due to the sulfur-sulfur lone pair interactions. The contracted S-S bond (1.979 Angstroms) and relatively high rotational barrier (19.29 kcal mol(-1) at the B3LYP/6-31G level) of the delta(OSSO) indicate the partial resonance-induced double bond character in this molecule. After ionization, the ground cationic-radical form of CF(3)C(O)OSSOC(O)CF(3)(*+) adopts a trans planar main-atom structure (delta(OSSO) = 180 degrees and delta(OCOS) = 0 degrees ) with C(2)(h) symmetry. The S-S bond elongates to 2.054 Angstroms, while the S-O bond shortens from 1.755 Angstroms in neutral form to 1.684 Angstroms in its corresponding cationic-radical form. The adiabatic ionization energy of 9.91 eV was obtained accordingly. The first two HOMOs correspond to the electrons mainly localized on the sulfur 3p lone pair MOs: 3ppi {36a (n(A)(S))](-1) and 3ppi [35b (n(B)(S), n(B)(O(C)(=)(O)))](-1), with an experimental energy separation of 0.16 eV. The first vertical ionization energy is determined to be 10.81 eV.