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Zhu B, Wu Z, Wang L, Lu B, Trabelsi T, Francisco JS, Zeng X. Matrix-isolated trifluoromethylthiyl radical: sulfur atom transfer, isomerization and oxidation reactions. Chem Commun (Camb) 2021; 57:12143-12146. [PMID: 34724519 DOI: 10.1039/d1cc04654c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
By high-vacuum flash pyrolysis of bis(trifluoromethyl)disulfane oxide (CF3S(O)SCF3) at 400 °C, the elusive trifluoromethylthiyl radical (CF3S˙) has been efficiently generated in the gas phase. Subsequent isolation of CF3S˙ in cryogenic matrixes (Ne, Ar, and N2) allows a first time characterization with IR and UV-vis spectroscopy by combining with computations at the CCSD(T)/aug-cc-pV(T + d)Z level. In addition to the photo-induced sulfur atom transfer (SAT) from CF3S˙ to N2 and CO and the isomerization to ˙CF2SF, the O2-oxidation via the intermediacy of the novel thiylperoxy radical CF3SOO˙ has been observed.
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Affiliation(s)
- Bifeng Zhu
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Fudan University, Shanghai 200433, China.
| | - Zhuang Wu
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Fudan University, Shanghai 200433, China.
| | - Lina Wang
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Fudan University, Shanghai 200433, China.
| | - Bo Lu
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Fudan University, Shanghai 200433, China.
| | - Tarek Trabelsi
- Department of Earth and Environment Science and Department of Chemistry, University of Pennsylvania, Pennsylvania, 19104-6243, USA.
| | - Joseph S Francisco
- Department of Earth and Environment Science and Department of Chemistry, University of Pennsylvania, Pennsylvania, 19104-6243, USA.
| | - Xiaoqing Zeng
- Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysts and Innovative Materials, Fudan University, Shanghai 200433, China.
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Berasategui M, Argüello GA, Burgos Paci MA. Gas-Phase Reaction between CF 2O and CF 3C(O)OH: Characterization of CF 3C(O)OC(O)F. J Phys Chem A 2019; 123:4671-4678. [PMID: 31046279 DOI: 10.1021/acs.jpca.9b00899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The thermal decomposition of trifluoroacetic acid and carbonyl fluoride (CF2O) has been extensively studied because of their importance in the oxidation of hydrochlorofluorocarbons in the atmosphere. We hitherto present the study of the thermal reaction between these two molecules. The reaction mechanism was studied using Fourier transform infrared spectroscopy in the temperature range of 513-573 K. The reaction proceeds homogeneously in the gas phase through the formation of a reaction intermediate, here characterized as CF3C(O)OC(O)F (detected for the first time in this work), the major final products being CF3C(O)F, HF, and CO2. We demonstrate that the reaction is first-order with respect to each reagent, second-order global and the mechanism consists of two steps, the first being the rate-determining one. The Ea = 110.1 ± 6.1 kJ mol-1 and A = (1.2 ± 0.2) × 10-12 cm3 molec-1 s-1 values were obtained from the experimental data. The low activation energy is explained by the hydrogen-bond interactions between the -OH group of the acid and the F atom of the CF2O. First-principles calculations at the G4MP2 level of theory were carried out to understand the dynamics of the decomposition. Thermodynamic activation values found for this reaction are as follows: Δ H⧧ = 105.6 ± 6.4 kJ mol-1, Δ S⧧ = -88.6 ± 9.7 J mol-1 K-1, and Δ G⧧ = 153.7 ± 13.5 kJ mol-1. The comparison between theory and experimental results showed excellent similarities, thus strengthening the proposed mechanism.
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Affiliation(s)
- Matias Berasategui
- Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET-UNC, Departamento de Físico Química, Facultad de Ciencias Químicas , Universidad Nacional de Córdoba , Ciudad Universitaria , X5000HUA Córdoba , Argentina
| | - Gustavo A Argüello
- Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET-UNC, Departamento de Físico Química, Facultad de Ciencias Químicas , Universidad Nacional de Córdoba , Ciudad Universitaria , X5000HUA Córdoba , Argentina
| | - Maxi A Burgos Paci
- Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET-UNC, Departamento de Físico Química, Facultad de Ciencias Químicas , Universidad Nacional de Córdoba , Ciudad Universitaria , X5000HUA Córdoba , Argentina
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Berasategui M, Argüello GA, Burgos Paci MA. Reaction of Methyl Fluoroformyl Peroxycarbonate (FC(O)OOC(O)OCH 3) with Cl Atoms: Formation of Hydro-ChloroFluoro-Peroxides. J Phys Chem A 2017; 121:7469-7476. [PMID: 28929761 DOI: 10.1021/acs.jpca.7b07449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The products following Cl atom initiated reactions of FC(O)OOC(O)OCH3 in 50-760 Torr of N2 at 296 K were investigated using FTIR. Reaction of Cl atoms with methyl fluoroformyl peroxycarbonate proceeds mainly via attack at the methyl group, forming FC(O)OOC(O)OCH2• radicals. Further reaction of this kind of radical with Cl2 forms three new compounds: FC(O)OOC(O)OCH2Cl, FC(O)OOC(O)OCHCl2, and FC(O)OOC(O)OCCl3, whose existence was characterized experimentally by FTIR spectroscopy assisted by ab initio calculations at the B3LYP/6-31++G(d,p) level. Relative rate techniques were used to measure k(Cl+FC(O)OOC(O)OCH3) = (4.0 ± 0.4) × 10-14 cm3 molecule-1 s-1 and k(Cl+FC(O)OOC(O)OCH2Cl) = (3.2 ± 0.3) × 10-14 cm3 molecule-1 s-1. When the reaction is run in the presence of oxygen, the paths giving chlorinated peroxide formation are suppressed, and oxidation to (mainly) CO2 and HCl takes place through highly oxidized intermediates with lifetimes long enough to be detected by FTIR spectroscopy.
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Affiliation(s)
- Matias Berasategui
- Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET-UNC, Departamento de Físico Química, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba , Ciudad Universitaria, X5000HUA Córdoba, Córdoba, Argentina
| | - Gustavo A Argüello
- Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET-UNC, Departamento de Físico Química, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba , Ciudad Universitaria, X5000HUA Córdoba, Córdoba, Argentina
| | - Maxi A Burgos Paci
- Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET-UNC, Departamento de Físico Química, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba , Ciudad Universitaria, X5000HUA Córdoba, Córdoba, Argentina
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Berasategui M, Burgos Paci MA, Argüello GA. Properties and thermal decomposition of the hydro-fluoro-peroxide CH₃OC(O)OOC(O)F. J Phys Chem A 2014; 118:2167-75. [PMID: 24548043 DOI: 10.1021/jp407871x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The thermal decomposition of methyl fluoroformyl peroxycarbonate CH3OC(O)OOC(O)F was studied in the range of 30- 96 °C using FTIR spectroscopy to follow the course of the reaction in the presence of either N2, O2, or CO as bath gases. The rate constants of the homogeneous first-order process fit the Arrhenius equation k(exp) = (5.4 ± 0.2) × 10(14) exp[-(27.1 ± 0.6 kcal mol(-1)/RT)] (in units of s(-1)). A complete mechanism of decomposition is presented. An experimental O-O bond energy of 27 ± 1 kcal mol(-1) was obtained. The products observed when N2 or O2 are used as bath gases were CO2, CO, HF, and CH3OC(O)H, while in the presence of CO, CH3OC(O)F was also observed. Transition state ab initio calculations were carried out to understand the dynamics of the decomposition. Additionally, thermodynamic properties of the atmospherically relevant CH3OCO2• radical were calculated. The heat of formation, ΔH°(f 298), obtained for CH3OCO2• and CH3OC(O)OOC(O)F, were 78 ± 3 kcal mol(-1) and 191 ± 5 kcal mol(-1), respectively.
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Affiliation(s)
- Matías Berasategui
- Instituto de Investigaciones en Físico Química de Córdoba (INFIQC) CONICET-UNC, Departamento de Físico Química, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria , X5000HUA Córdoba, Córdoba, Argentina
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Waltman R. Evidence for the unimolecular decomposition of CF3OCF3 to COF2 and CF4 by high energy irradiation. J Fluor Chem 2013. [DOI: 10.1016/j.jfluchem.2013.08.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Manetti MD, Burgos Paci MA, Argüello GA. Trifluoromethyl Fluoroformyl Trioxicarbonate, CF3OC(O)OOOC(O)F: The First Nonsymmetric Acyl Trioxide. J Phys Chem A 2009; 113:8523-8. [DOI: 10.1021/jp9022772] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Martín D. Manetti
- INFIQC, Departamento de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina
| | - Maximiliano A. Burgos Paci
- INFIQC, Departamento de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina
| | - Gustavo A. Argüello
- INFIQC, Departamento de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina
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Nguyen MT, Matus MH, Ngan VT, Haiges R, Christe KO, Dixon DA. Energetics and Mechanism of the Decomposition of Trifluoromethanol. J Phys Chem A 2008; 112:1298-312. [DOI: 10.1021/jp709796n] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Minh Tho Nguyen
- Department of Chemistry, The University of Alabama, Shelby Hall, Tuscaloosa, Alabama 35487-0336, Department of Chemistry, University of Leuven, B-3001 Leuven, Belgium, and Loker Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661
| | - Myrna H. Matus
- Department of Chemistry, The University of Alabama, Shelby Hall, Tuscaloosa, Alabama 35487-0336, Department of Chemistry, University of Leuven, B-3001 Leuven, Belgium, and Loker Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661
| | - Vu Thi Ngan
- Department of Chemistry, The University of Alabama, Shelby Hall, Tuscaloosa, Alabama 35487-0336, Department of Chemistry, University of Leuven, B-3001 Leuven, Belgium, and Loker Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661
| | - Ralf Haiges
- Department of Chemistry, The University of Alabama, Shelby Hall, Tuscaloosa, Alabama 35487-0336, Department of Chemistry, University of Leuven, B-3001 Leuven, Belgium, and Loker Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661
| | - Karl O. Christe
- Department of Chemistry, The University of Alabama, Shelby Hall, Tuscaloosa, Alabama 35487-0336, Department of Chemistry, University of Leuven, B-3001 Leuven, Belgium, and Loker Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661
| | - David A. Dixon
- Department of Chemistry, The University of Alabama, Shelby Hall, Tuscaloosa, Alabama 35487-0336, Department of Chemistry, University of Leuven, B-3001 Leuven, Belgium, and Loker Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089-1661
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Beckers H, Garcia P, Willner H, Argüello G, Cobos C, Francisco J. Side-on- oder End-on-Koordination von O2 am FSO3-Radikal: Matrixisolation und Ab-initio-Untersuchung von FSO5. Angew Chem Int Ed Engl 2007. [DOI: 10.1002/ange.200604346] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Beckers H, Garcia P, Willner H, Argüello GA, Cobos CJ, Francisco JS. Side-On versus End-On Bonding of O2 to the FSO3 Radical: Matrix Isolation and Ab Initio Study of FSO5. Angew Chem Int Ed Engl 2007; 46:3754-7. [PMID: 17431931 DOI: 10.1002/anie.200604346] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Helmut Beckers
- FB C--Anorganische Chemie, Bergische Universität Wuppertal, Gaussstrasse 20, 42097 Wuppertal, Germany
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Marenich AV, Boggs JE. Molecular Spectroscopy beyond the Born−Oppenheimer Approximation: A Computational Study of the CF3O and CF3S Radicals. J Phys Chem A 2007; 111:11214-20. [PMID: 17469808 DOI: 10.1021/jp070495f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This paper addresses some advances in the theoretical description of molecular spectroscopy beyond the Born-Oppenheimer adiabatic approximation. A solution of the nuclear dynamics problem complicated by the EE Jahn-Teller effect and spin-orbit coupling is considered for the case of the CF3O and CF3S radicals, all the model parameters being obtained solely from ab initio calculations without any adjustment to experimental numbers. Vibrational and vibronic model parameters were calculated at the equation-of-motion coupled cluster level of theory with basis sets of triple-zeta quality. The spin-orbit coupling in X 2E CF3O and CF3S was parametrized by means of a perturbative solution of the full Breit-Pauli spin-orbit operator. Spin-vibronic eigenvalues and eigenfunctions were computed in a basis set of products of electronic, electron spin, and vibrational functions. Results demonstrate the importance of explicit inclusion of the spin-orbit coupling and at least cubic Jahn-Teller terms in the model Hamiltonian for the high precision evaluation of spin-vibronic energy levels of CF3O and CF3S. The theoretical results support and complement the spectroscopic data observed for these species.
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Affiliation(s)
- Aleksandr V Marenich
- Institute for Theoretical Chemistry, Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712-0165, USA
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Burgos Paci MA, Argüello GA, García P, Willner H. Thermal Decomposition of the Perfluorinated Peroxides CF3OC(O)OOC(O)F and CF3OC(O)OOCF3. J Phys Chem A 2005; 109:7481-8. [PMID: 16834117 DOI: 10.1021/jp0528818] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Gas phase thermal decomposition of CF(3)OC(O)OOC(O)F and CF(3)OC(O)OOCF(3) was studied at temperatures between 64 and 98 degrees C (CF(3)OC(O)OOC(O)F) and 130-165 degrees C (CF(3)OC(O)OOCF(3)) using FTIR spectroscopy to follow the course of the reaction. For both substances, the decompositions were studied with N(2) and CO as bath gases. The rate constants for the decomposition of CF(3)OC(O)OOC(O)F in nitrogen and carbon monoxide fit the Arrhenius equations k(N)2 = (3.1 +/- 0.1) x 10(15) exp[-(29.0 +/- 0.5 kcal mol(-1)/RT)] and k(CO) = (5.8 +/- 1.3) x 10(15) exp[-(29.4 +/- 0.5 kcal mol(-1)/RT)], and that for CF(3)OC(O)OOCF(3) fits the equation k = (9.0 +/- 0.9) x 10(13) exp[-(34.0 +/- 0.7 kcal mol(-1)/RT)] (all in units of inverted seconds). Rupture of the O-O bond was shown to be the rate-determining step for both peroxides, and bond energies of 29 +/- 1 and 34.0 +/- 0.7 kcal mol(-1) were obtained for CF(3)OC(O)OOC(O)F and CF(3)OC(O)OOCF(3). The heat of formation of the CF(3)OCO(2)(*) radical, which is a common product formed in both decompositions, was calculated by ab initio methods as -229 +/- 4 kcal mol(-1). With this value, the heat of formation of the title species and of CF(3)OC(O)OOC(O)OCF(3) could in turn be obtained as Delta(f) degrees (CF(3)OC(O)OOC(O)F) = -286 +/- 6 kcal mol(-1), Delta(f) degrees (CF(3)OC(O)OOCF(3)) = -341 +/- 6 kcal mol(-1), and Delta(f) degrees (CF(3)OC(O)OOC(O)OCF(3)) = -430 +/- 6 kcal mol(-1).
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Affiliation(s)
- Maximiliano A Burgos Paci
- INFIQC, Departamento de Físico Química, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina
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Souzy R, Ameduri B, von Ahsen S, Willner H, Argüello GA. Use of bis(trifluoromethyl)peroxy dicarbonate as initiator in the radical homopolymerisation of vinylidene fluoride (VDF) and copolymerisation of VDF with hexafluoropropylene. J Fluor Chem 2003. [DOI: 10.1016/s0022-1139(03)00137-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Trautner F, Gholivand K, García P, Willner H, Erben MF, Della Védova CO, Oberhammer H. Perfluoromethyl fluorocarbonyl peroxide, CF3OOC(O)F: structure, conformations, and vibrational spectra studied by experimental and theoretical methods. Inorg Chem 2003; 42:3079-85. [PMID: 12716204 DOI: 10.1021/ic0262583] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The conformational properties and the geometric structure of perfluoromethyl fluorocarbonyl peroxide, CF(3)OOC(O)F, have been studied by matrix IR spectroscopy, gas electron diffraction, and quantum chemical calculations (HF, B3LYP, and MP2 methods with 6-311G* basis sets). Matrix IR spectra imply a mixture of syn and anti conformers (orientation of the C=O bond relative to the O-O bond) with DeltaH degrees = H(anti) degrees - H(syn) degrees = 2.16(22) kcal/mol. At room temperature, the contribution of the anti rotamer is about 3.0%. The O-O bond (1.422(15) A) is within the experimental uncertainties equal to those in related symmetrically substituted peroxides CF(3)OOCF(3) and FC(O)OOC(O)F (1.419(20) and 1.419(9) A, respectively), and the dihedral angle delta(COOC) (111(5) degrees ) is intermediate between the values in these two compounds (123(4) degrees and 83.5(14) degrees, respectively).
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Affiliation(s)
- Frank Trautner
- Institut für Physikalische und Theoretische Chemie, Universität Tübingen, D-72076 Tübingen, Germany
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Burgos Paci MA, García P, Malanca FE, Argüello GA, Willner H. Synthesis and characterization of trifluoromethyl fluoroformyl peroxycarbonate, CF3OC(O)OOC(O)F. Inorg Chem 2003; 42:2131-5. [PMID: 12639151 DOI: 10.1021/ic0261528] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis of CF(3)OC(O)OOC(O)F is accomplished by the photolysis of a mixture of (CF(3)CO)(2)O, FC(O)C(O)F, CO, and O(2) at -15 degrees C using a low-pressure mercury lamp. The new peroxide is obtained in pure form in low yield after repeated trap-to-trap condensation and is characterized by NMR, IR, Raman, and UV spectroscopy. Geometrical parameters were studied by ab initio methods [B3LYP/6-311+G(d)]. At room temperature, CF(3)OC(O)OOC(O)F is stable for many days in the liquid or gaseous state. The melting point is -87 degrees C, and the boiling point is extrapolated to 45 degrees C from the vapor pressure curve log p = 8.384 - 1715/T (p/mbar, T/K). A possible mechanism for the formation of CF(3)OC(O)OOC(O)F is discussed, and its properties are compared with those of related compounds.
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Affiliation(s)
- Maximiliano A Burgos Paci
- INFIQC, Departamento de Físico Química, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000 Córdoba, Argentina
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Abstract
Low pressure flash thermolysis of different precursor molecules containing-ClO, -ClO3 or -OClO3 yield, when highly diluted in Ne or O2 and subsequent quenching of the products in a matrix at 5 or 15 K, ClOx (x = 1, 3, 4) radicals, respectively. If Ne or O2 gas is directed over solid ClO2 at -120 degrees C and the resulting gas mixtures are immediately deposited as a matrix, a high fraction of (OClO)2 is trapped. This enables recording of IR and UV spectra of weakly bonded (OClO)2 dimers and detailed studying of their photochemistry. For Ne or O2 matrix isolated ClO radicals the vibrational wavenumbers and electronic transitions are only slightly affected compared with the gas phase. In this study strong evidence is found for long lived ClO in the electronically excited 2 [symbol: see text] 1/2 state. A comprehensive IR study of Ne matrix isolated ClO3 (fundamentals at 1081, 905, 567, 476 cm-1) yield i) a reliable force field; ii) a OClO bond angle of alpha e = 113.8 +/- 1 degrees and iii) a ClO bond length of 148.5 +/- 2 pm in agreement with predicted data from quantum chemical calculations. The UV/Vis spectrum of ClO3 isolated in a Ne matrix (lambda max at 32,100 and 23,150 cm-1) agrees well with the photoelectron spectrum of ClO3- and theoretical predictions. The origin of the structured high energy absorption is at 22,696 cm-1 and three fundamentals (794, 498, 280 cm-1) are detected in the C2E state. By photolysis of ClO3 with visible light the complex ClO.O2 with ClO in the 2 [symbol: see text] 1/2 state is formed. In an extended spectroscopic study of the elusive ClO4 radical, isolated in a Ne or O2 matrix, three additional IR bands, a complete UV spectrum and a strong interaction with O2 are found. This leads to the conclusion that ClO4 exhibits C2v or Cs symmetry with a shallow potential minimum and forms with O2 the previously unknown peroxy radical O3ClO-O2. All these results are discussed in the context of recent developments in the chemistry and spectroscopy of the important and interesting ClOx (x = 1-4) family of radicals.
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Affiliation(s)
- Rodion Kopitzky
- Fakultät 4, Anorganische Chemie Gerhard-Mercator Universität Duisburg, Lotharstrasse 1 47048 Duisburg, Germany
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Kinetics of the thermal decomposition of bis(trifluoromethyl) peroxydicarbonate, CF3OC(O)OOC(O)OCF3. INT J CHEM KINET 2002. [DOI: 10.1002/kin.10099] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Malanca FE, Burgos Paci M, Argüello GA. Photochemistry of perfluoroacyl halides in the presence of O2 and CO. J Photochem Photobiol A Chem 2002. [DOI: 10.1016/s1010-6030(02)00089-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Photochemistry of fluorinated compounds: reaction between FCO and CF3CF2 radicals. J Photochem Photobiol A Chem 2002. [DOI: 10.1016/s1010-6030(02)00006-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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