76-16-4Relevant articles and documents
Coomber, J. W.,Whittle, E.
, p. 1394 - 1401 (1967)
Kinetc Study of Infrared Multiphoton Dissociation. Two-Frequency Irradiation of CF3(13)COCF3 molecules at Natural Abundance
Hackett, P. A.,Gauthier, M.,Nip, W. S.,Willis, C.
, p. 1147 - 1152 (1981)
The characteristics of the infrared multiphoton excitation of hexafluoroacetone in region I and region II have been investigated by photolysis with two CO2 laser pulses.The sequenced pulses were at different frequencies and had different fluences so that effects arising in the two regions could be clearly separated.We have studied the isotopically selective dissociation of CF3(13)COCF3 molecules, present at their natural abundance, as a function of five parameters, the frequency of the dissociating second pulse, the fluence of both pulses, the substrate pressure, and the interpulse delay.The results give a picture of the kinetic behavior of vibrationally excited hexafluoroacetone molecules produced in the presence of strong infrared fields.
Dobis et al.
, p. 278 (1968)
Time-Resolved Tunable Diode Laser Detection of Products of the Infrared Multiphoton Dissociation of Hexafluoroacetone: A Line-Strength and Band-Strength Measurement for CF3
Orlando, J. J.,Smith, D. R.
, p. 5147 - 5150 (1988)
This paper describes the time resolved detection of CF3, C2F6, and CO following the infrared multiphoton dissociation of hexafluoroacetone.The primary photolysis mechanism has been estalished as follows: (CF3)2CO -> 2CF3 + CO; 2CF3 -> C2F6.Determination of the CO and C2F6 formed in a single photolysis pulse leads to a measure of an infrared line strength and ν3 band strength for CF3.Quantification of the CF3 in this manner allows a study of its reaction kinetics.The reactions of CF3 with added O2 and NO were found to have third-body rate constants of (2.1 +/- 0.5) * 10-29 and (2.8 +/- 0.7) * 10-29 cm6 molecule-2 s-1, respectively, at room temperature in the presence of 600 mTorr of hexafluoroacetone.
Varetti,Aymonino
, p. 680 (1967)
Intensity and Pressure Effects in Infrared Multiphoton Dissociation. Phitilysis of Hexafluoroacetone and Trifluoromethyl Bromide with 2-ns Laser Pulses
Hackett, P. A.,Malatesta, V.,Nip, W. S.,Willis, C.,Corkum, P. B.
, p. 1152 - 1155 (1981)
We have carried out a study of the effect pulse length on the infrared multiphoton dissociation of hexafluoroacetone.A constant fluence of 1.8 J cm-2 was used, for both short-pulse (2-ns fwhm) and long-pulse (ca. 120 ns fwhm, 5-μs tail, gain swithed, self-mode-locked TEA CO2 laser) irradiation.The dissociation yields are very significantly different both in their magnitude and in their dependence on pressure of substrate of of added hexafluoroethane.At moderate pressures (>0.2 torr) collisional effects dominate the long-pulse irradiation.Possible explanations of these effects are discussed.A study of the isotopically selective dissociation of trifluoromethyl bromide revealed that, although the intensity is high, isotopic selectivity (α ca. 20) is retained.
Photoinduced Sulfur-Nitrogen Bond Rotation and Thermal Nitrogen Inversion in Heterocumulene OSNSO
Wu, Zhuang,Feng, Ruijuan,Xu, Jian,Lu, Yan,Lu, Bo,Yang, Tao,Frenking, Gernot,Trabelsi, Tarek,Francisco, Joseph S.,Zeng, Xiaoqing
, p. 1231 - 1234 (2018/02/09)
An exotic ternary S, N, O heterocumulene OSNSO in syn-syn (A) and syn-anti (B) conformations has been generated in the gas phase through flash vacuum pyrolysis of CF3S(O)NSO at 700 K. Upon visible light irradiation (570 ± 20 or 532 nm), both A and B, isolated in cryogenic matrices (N2, Ne, Ar, and Kr, a higher-energy anti-anti conformer (C). The reverse conformational transformation occurs either through S=N bond rotation (C to A and B) under visible light irradiation (400 ± 20 nm) at 2.8 K or through thermal nitrogen inversion (C to A) in the temperature range of 20-30 K, for which an exceptionally low activation barrier of 1.18 ± 0.07 kcal mol-1 has been experimentally determined.
A method of preparing hexafluoroethane at high temperature
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Paragraph 0036; 0037; 0038, (2017/02/17)
The invention relates to a method of preparing hexafluoroethane at high temperature and belongs to the technical field of fluorine chemical engineering. The method includes adding cobaltous fluoride into a reactor, controlling the temperature of the reactor to be 350-450 DEG C and pressure of the reactor to be 0.1-0.15 MPa, adding a gas mixture of nitrogen trifluoride and nitrogen and pentafluoroethane, with the gas space velocity in a cobaltous oxide bed layer being 0.2-5 /min, and discharging a reaction product from the reactor to obtain the hexafluoroethane. Raw materials used in the method are safe. The method is safe in operation, high in product yield and suitable for large-scale industrial production.
Preparation method of electronic grade hexafluoroethane
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Paragraph 0025-0028; 0032-0035; 0039-0042; 0045-0048; 0053, (2017/06/02)
The invention relates to a preparation method of electronic grade hexafluoroethane. The preparation method comprises the following steps: a hydrogen fluoride gas and a chloropentafluoroethane gas enter a reactor containing a novel catalyst, and undergo a reaction at 300-500 DEG C at an air speed of 1-5 BV/h to prepare crude hexafluoroethane, wherein a molar ratio of the hydrogen fluoride gas to the chloropentafluoroethane gas is 1-3:1; and the crude hexafluoroethane is rectified, the rectified hexafluoroethane enters an adsorption tower containing an adsorbent and is adsorbed to obtain the highly-pure hexafluoroethane product.