Free Radicals by Mass Spectrometry. IX. Ionization Potentials of CF3and CCl3Radicals and Bond Dissociation Energies in Some Derivatives
摘要:
The vertical ionization potentials of CF3 and CCl3 radicals, as measured by electron impact, are 10.10±0.05 and 8.78±0.05 v respectively. From the appearance potentials of the CF3+ and CCl3+ ions from derivatives, the heats of formation of CF3 and CCl3 radicals were found to be —117±2 kcal/mole and +13.4±3 kcal/mole respectively, assuming that no excess energy was included in the appearance potentials. From this data and other heats of formation the following bond dissociation energies (in kcal/mole) have been evaluated: D(CCl3−H)=88.9±3D(CCl3−F)=102±7D(CCl3−Cl)=67.9±3D(CCl3−Br)=49.5±3D(CF3−H)=103±4D(CF3−F)=121±4D(CF3−Cl)=83±3
chloropicrin in air at 1 atm was performed in a 6-m3 photochemical reaction chamber with a combination of Xe arc lamps and Pyrex filters as a light source. Phosgene was obtained as one of the main products with a yield of unity. No nitrosylchloride was observed, which supports the C–N scission mechanism for the photolysis. Photochemical ozone formation was enhanced when chloropicrin was added to the
New systems for classical nitrosohalogenation of alkenes 2. Generation of nitrosyl chloride in AgNO2-SOCl2 and AgNO3-SOCl2 systems
作者:O. B. Bondarenko、A. Yu. Gavrilova、V. N. Tikhanushkina、N. V. Zyk
DOI:10.1007/s11172-006-0089-2
日期:2005.9
Study of the reactions of compounds of the norbornene series demonstrated that the AgNO2-SOCl2 and AgNO3-SOCl2 systems serve as nitrosochlorinating agents under the conditions of electrophilic addition. X-ray diffraction study showed that dimerization of cis-exo-2-chloro-3-nitrosobicyclo[2.2.1]heptane occurs heterostereospecifically. The origin of the active principle of the reagents is discussed.
Photofragmentation of Nitryl Chloride in the Ultraviolet Regime and Vacuum Ultraviolet Regime
作者:J. Plenge、R. Flesch、M. C. Schürmann、E. Rühl
DOI:10.1021/jp0044330
日期:2001.5.1
corresponding to the photon energy range 11.3 eV ≤ E ≤ 22.5 eV), where pulsed radiation is used to excite the neutral molecule in the gas phase. The neutral photolysis products that are formed upon UV photolysis are subsequently probed by photoionization mass spectrometry by using time-correlated tunable laser-produced plasma VUV radiation. UV-pump/VUV-probe experiments allow us to identify two primary photolysis
with subsequent experiments conducted with a xenon lamp at are reported. Formation of cis and trans ClONO in equilibrium with ClNO2 is observed after irradiation at 266 nm. At the transformation of trans ClONO into cis ClONO occurs. On prolonged photolysis at 266 nm, ClONO dissociates into ClON and atom and into ClO+NO as evidenced in reactive matrices (solid oxygen and nitrogen).
An infrared study of the UV photolysis of chlorine nitrate trapped in various matrices at 11 K
作者:Armelle De Saxce、Louise Schriver
DOI:10.1016/0009-2614(92)85016-4
日期:1992.11
Photolysis of matrix isolated chlorine nitrate in argon matrix assisted by reactive matrices (solid nitrogen and oxygen) at 11 K have been carried out by visible and ultraviolet light in the 800—250 nm range. The product identification and relative measurements of the species time evolution were made by Fourier transform infrared spectrometry. Below 300 nm, two main dissociation channels are evidenced
借助在800-250 nm范围内的可见光和紫外光,在11 K下由反应性基质(固体氮和氧)辅助下的氩气基质中的基质分离的硝酸氯光解。用傅立叶变换红外光谱法对产物的时间演化进行产物鉴定和相对测量。在300 nm以下,有两个主要的解离通道被证明分别导致ClNO + O 2和ClONO +O。重组笼过程在基质中发生,并且获得的结果与气相研究部分不同,但提供了有关冷凝相系统(例如极地平流层云表面)中可能发生的光反应的信息。