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Ge M, Yao L, Wang D. Electronic structure and photoionization and dissociation processes of bis(trifluoromethoxy)disulfurylperoxide, CF3OS(O)2OOS(O)2OCF3. J Phys Chem A 2007; 111:13425-31. [PMID: 18052262 DOI: 10.1021/jp0753326] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this work, we present a complete study of the photoionization and dissociation processes for bis(trifluoromethoxy)disulfurylperoxide, CF3OS(O)2OOS(O)2OCF3, which was generated by UV photolysis of a mixture of (CF3CO)2O, SO2, and O2 at a low temperature. The reaction product was detected and characterized by the photoelectron (PE) and photoionization mass spectroscopy (PIMS). For comparison, the geometric and electronic structures of CF3S(O)2OS(O)2CF3 (a), CF3OS(O)2OS(O)2OCF3 (b), and CF3OS(O)2OOS(O)2OCF3 (c) were investigated by the combination of experiments and theoretical studies. The PES results show that the outer electrons residing in nO(S=O) of b and c are more tightly bound than those of a. It is worthwhile mentioning that drastic changes occur in the geometry of c after one-electron ionization. The neutral molecule exhibits a gauche structure with the SOOS dihedral angle of 124.4 degrees . The first ionization process happens on the O-O antibonding orbital. The remarkable geometric changes between the ground-state molecule and cation are computed to be the gauche-to-trans rotation of deltaSOOS and the prolongation of the S1-O1 single bond length. According to the calculated bond dissociation energies, the dissociation process was discussed. The calculated results indicate that once the parent ion is formed, the dissociation of the S1-O1 bond to form CF3OSO2+ is inevitable.
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Affiliation(s)
- Maofa Ge
- State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100080, People's Republic of China.
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Yao L, Du L, Ge M, Wang D. Experimental and theoretical studies of the electronic structure and the ionization and dissociation processes of trifluoromethyl peroxynitrate. J Chem Phys 2007; 126:184301. [PMID: 17508797 DOI: 10.1063/1.2734971] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In this work, we present a complete study of the ionization and dissociation processes for trifluoromethyl peroxynitrate (CF3OONO2). CF3OONO2 was generated by UV photolysis of a mixture of (CF3CO)2O, NO2, and O2. The product was detected and characterized by the photoelectron spectroscopy (PES) and photoionization mass spectroscopy (PIMS). The geometric and electronic structures of CF3OONO2 were investigated by the combination of experiments and the density functional and ab initio calculations. It is worthwhile mentioning that drastic changes occur in the geometry of CF3OONO2 after ionization. Due to the removal of one electron from the O-N sigma bond, the COON dihedral angle changes to 180 degrees and as a result, the nonplanar structure becomes planar. And the O-N single bond length increases remarkably, with the positive charge most localized on the NO2 moiety. The experimental first vertical ionization potential is 12.39 eV. Based on the calculated bond dissociation energies, the dissociation pathway was predicted. The calculated results explain the ion intensities observed in the photoionization mass spectrum. The dissociation of O-N single bond is found to be the most favored of the possible dissociation paths for CF3OONO2+.
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Affiliation(s)
- Li Yao
- Beijing National Laboratory for Molecular Science (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, People's Republic of China
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Erben MF, Della Védova CO. Dramatic changes in geometry after ionization: experimental and theoretical studies on the electronic properties of fluorocarbonyl (mono-, di-, and tri-) sulfur compounds. Inorg Chem 2002; 41:3740-8. [PMID: 12099879 DOI: 10.1021/ic020046o] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this work, we present a complete study on He I photoelectron spectroscopy (PES) for the fluorocarbonyl mono-, di-, and trisulfur compounds FC(O)SCl, FC(O)SSCH(3), and FC(O)SSSC(O)F. After optimizations of the structure for stable conformers at different levels of theory, a complete theoretical study involving the calculation of the ionization energies using orbital valence Green's functional (OVGF) was performed. Calculations of radical-cationic forms were carried out in order to compare their properties with those of the neutral molecules. The first IP values are 10.7, 9.0, and 10.5 eV for FC(O)SCl, FC(O)SSCH(3), and FC(O)SSSC(O)F, respectively. The groups bonded to the S atom mainly influence the ionizations originating from the sulfur lone pairs. A wide electronic delocalization in the FC(O)S moiety can be deduced from experimental and theoretical results, which leads to a strong energetic stabilization of the n' '(S) (sulfur lone pair pi orbital). Other conclusions relate to effects on the substituents attached to the S atom and the importance of the molecular planarity in the orbital stabilization of the FC(O)S moiety for the neutral molecules. It is worthwhile mentioning that FC(O)SCl retains its planar structure after ionization, but drastic changes occur in the geometry of both FC(O)SSCH(3) and FC(O)SSSC(O)F. The FC(O)SSCH(3) molecule adopts a heavy atom planar structure after ionization. The FC(O)SSS moiety becomes a planar form after the ionization of the FC(O)SSSC(O)F molecule, whereas the second C(O)F group maintains its original conformation with respect to the SSS group.
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Affiliation(s)
- Mauricio F Erben
- CEQUINOR (CONICET-UNLP), Departamento de Quimica, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 47 esq. 115 (1900) C. C. 962 La Plata, República Argentina
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Steudel R, Drozdova Y, Miaskiewicz K, Hertwig RH, Koch W. How Unstable are Thiosulfoxides? An ab Initio MO Study of Various Disulfanes RSSR (R = H, Me, Pr, All), Their Branched Isomers R2SS, and the Related Transition States1,2. J Am Chem Soc 1997. [DOI: 10.1021/ja9624026] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ralf Steudel
- Contribution from the Institut für Anorganische und Analytische Chemie, Technische Universität Berlin, Sekr. C2, D-10623 Berlin, Germany, Pacific Northwest Laboratories, K1-96, Richland, Washington 99352, and Institut für Organische Chemie, Technische Universität Berlin, Sekr. C3, D-10623 Berlin, Germany
| | - Yana Drozdova
- Contribution from the Institut für Anorganische und Analytische Chemie, Technische Universität Berlin, Sekr. C2, D-10623 Berlin, Germany, Pacific Northwest Laboratories, K1-96, Richland, Washington 99352, and Institut für Organische Chemie, Technische Universität Berlin, Sekr. C3, D-10623 Berlin, Germany
| | - Karol Miaskiewicz
- Contribution from the Institut für Anorganische und Analytische Chemie, Technische Universität Berlin, Sekr. C2, D-10623 Berlin, Germany, Pacific Northwest Laboratories, K1-96, Richland, Washington 99352, and Institut für Organische Chemie, Technische Universität Berlin, Sekr. C3, D-10623 Berlin, Germany
| | - Roland H. Hertwig
- Contribution from the Institut für Anorganische und Analytische Chemie, Technische Universität Berlin, Sekr. C2, D-10623 Berlin, Germany, Pacific Northwest Laboratories, K1-96, Richland, Washington 99352, and Institut für Organische Chemie, Technische Universität Berlin, Sekr. C3, D-10623 Berlin, Germany
| | - Wolfram Koch
- Contribution from the Institut für Anorganische und Analytische Chemie, Technische Universität Berlin, Sekr. C2, D-10623 Berlin, Germany, Pacific Northwest Laboratories, K1-96, Richland, Washington 99352, and Institut für Organische Chemie, Technische Universität Berlin, Sekr. C3, D-10623 Berlin, Germany
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Bock H, Stein U, Semkow A. Photoelektronen-Spektren und Moleküleigenschaften, 95. 1,2-Dithiolan – Bindungsmodell für α-Liponsäure. ACTA ACUST UNITED AC 1980. [DOI: 10.1002/cber.19801131009] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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