Reaction Of Fluorine Atoms Research Articles

Reaction of fluorine atoms with nitromethane. Vibrational spectra of the addition complex and of the nitromethyl free radical

Reaction of fluorine atoms with nitromethane. Vibrational spectra of the addition complex and of the nitromethyl free radical

Extent of the displacement route in the reactions of fluorine atoms with ethylene, vinyl chloride, and vinyl bromide

The chemical branching of three fluorine-atom reactions, those with C/sub 2/H/sub 4/, C/sub 2/H/sub 3/Cl, and C/sub 2/H/sub 3/Br, was studied in real-time experiments using a tubular reactor coupled to a photoionization mass spectrometer. The fluorine atoms were generated by the CO/sub 2/-laser induced secondary photolysis of C/sub 6/F/sub 5/Cl which also appears to produce tetrafluorobenzyne (c-C/sub 6/F/sub 4/). The measured fractional extents that the three reactions studied proceed by a displacement route at 295 K (to yield C/sub 2/H/sub 3/F+X) are 0.65 (+/-0.06), 0.72 (+/-0.14), and 0.72 (+/-0.14) for C/sub 2/H/sub 4/, C/sub 2/H/sub 3/Cl, and C/sub 2/H/sub 3/Br respectively.

Non-RRKM decomposition of chemically activated radicals: Reaction of fluorine atoms with tetraallyl germanium

Thermal F atoms react with gaseous (CH 2CHCH 2) 4Ge to produce CH 2CHF through dissociation of the (CH 2CHCH 2) 3-GeCH 2CHFCH 2 * radical. The rapid decomposition is attributed to non-RRKM behavior with excitation energy largely confined to the CH 2CHFCH 2 side group. The central atoms mass effect found in linear seven-atom trajectory calculations has not yet appeared in (CH 2CHCH 2) 4M with the replacement of Sn by Ge.

The first band in the He(I) photoelectron spectrum of the CH 2Cl free radical

The fluorine atom reaction with CH 3Cl provides the CH 2Cl free radical for observation of a structured photoelectron band at 8.88 ± 0.01 eV vertical ionization energy with 1020 ± 40 cm −1 vibrational intervals. This spacing is appropriate for the CCl fundamental in CH 2Cl + based on increase (pp) π bonding in the cation as compared to the free radical.

Vibrational energy disposal in reactions of fluorine atoms with hydrides of groups III, IV and V

Abstract The HF infrared chemiluminescence from the reactions of F atoms with B 2 H 6 , CH 4 , CH 3 F, CH 2 F 2 , CH 2 Cl 2 , CH 3 ONO. CH 3 NO 2 , NH 3 (and ND 3 ). PH 3 and HNCO has been observed from a 300 K flowing-afterglow reactor. Experiments were done for a range of CH 4 and F atom concentrations to identify conditions which were free of vibrational relaxation and secondary reactions, and these conditions were used to assign initial HF( v ) vibrational distributions for each reaction. The emission intensity from each reaction also was compared to that from CH 4 in order to obtain the relative HF formation rate constants at 300 K. Since the absolute rate constant for F + CH 4 is well established, the combination of all of these data provides absolute rate constants for HF( v ) formation at 300 K. The ND 3 reaction was studied to obtain information on more vibrational levels in order to better estimate the HF( v = 0) and DF( v = 0) components of the ammonia distributions. With NH 3 and ND 3 there is no significant isotope effect on the energy disposal. Except for NHCO, for which an addition-elimination channel is possible, the HF( v ) distributions are inverted and f v > = 0.60. Differences between the HF( v ) distributions reported here and some other reports in the literature are noted: the present data are discussed as representative of direct H atom abstraction for 300 K Boltzmann conditions. The HCl infrared chemiluminescence from the F + CHCl 2 secondary reaction also was observed; the HCl( v ) distribution was v 1 : v 2 : v 3 : v 4 : v 5 - 0.47: 0.23: 0.18: 0.08: 0.04.

Vacuum ultraviolet photoelectron spectroscopy of transient species

The He(I) photoelectron spectrum of the N3(X 2H) radical, produced by the rapid gas phase reaction of fluorine atoms with hydrazoic acid, has been recorded. Three bands were observed corresponding to ionization of N3(X 2H) to the N3 + X 3Σ−, 1Δ and 1Σ+ states. The vertical ionization energies to the observed ionic states were compared with those obtained from ΔSCF ab initio calculations. Evidence is presented to show that the major pathway of the F+HN3 reaction occurs via a long-lived intermediate and involves abstraction of a hydrogen atom yielding vibrationally excited HF and the N3 radical. Consideration of both the photoelectron data and a recent chemiluminescence study of the reaction has led to some re-interpretation of the latter results.

ChemInform Abstract: REACTION OF FLUORINE ATOMS WITH BENZENE. VIBRATIONAL SPECTRUM OF THE 1‐FLUOROCYCLOHEXADIENYL RADICAL INTERMEDIATE TRAPPED IN SOLID ARGON

Chemischer InformationsdienstVolume 13, Issue 24 Preparative Organic Chemistry ChemInform Abstract: REACTION OF FLUORINE ATOMS WITH BENZENE. VIBRATIONAL SPECTRUM OF THE 1-FLUOROCYCLOHEXADIENYL RADICAL INTERMEDIATE TRAPPED IN SOLID ARGON M. E. JACOX, M. E. JACOXSearch for more papers by this author M. E. JACOX, M. E. JACOXSearch for more papers by this author First published: June 15, 1982 https://doi.org/10.1002/chin.198224143AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume13, Issue24June 15, 1982 RelatedInformation

Kinetics of the F , F 2 / B 4 C Gasification Reactions

Intrinsic kinetics for the reactions were measured using a low pressure duct flow reactor technique with specimen gasification rates deduced from duct mass loss rates. Reaction of atomic fluorine was studied by passing dilute mixtures through a 70W 2450 MHz microwave discharge upstream of the duct. Data were obtained between 740 and 1000 K at and 570–1000 K at . The reaction probability is independent of pressure and increases with temperature from to over the temperature range studied. The reaction probability increases from at 740 K to at 1000 K. These results are discussed along with available kinetic data on F and/or reaction with carbon, boron, carbides, and borides.

Reaction of atomic fluorine with silicon: The gas phase products

SiF2 and SiF4 have been identified as gas phase products of the reaction between atomic fluorine and silicon. Atomic fluorine is supplied by a low density molecular beam hitting a silicon target in a high vacuum. Reaction products were detected by mass spectrometric measurements. Activation energies for the production of SiF2 and SiF4 were found to be 0.09±0.02 and 0.15±0.02 eV/°K, respectively, in good agreement with the values measured by flowing afterglow techniques. The reaction probability for the reaction 4F+Si→SiF4 was found to be 0.016 at 100 °C.

Reaction of fluorine atoms with benzene. Vibrational spectrum of the 1-fluorocyclohexadienyl radical intermediate trapped in solid argon

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTReaction of fluorine atoms with benzene. Vibrational spectrum of the 1-fluorocyclohexadienyl radical intermediate trapped in solid argonMarilyn E. JacoxCite this: J. Phys. Chem. 1982, 86, 5, 670–675Publication Date (Print):March 1, 1982Publication History Published online1 May 2002Published inissue 1 March 1982https://doi.org/10.1021/j100394a016RIGHTS & PERMISSIONSArticle Views61Altmetric-Citations19LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (760 KB) Get e-Alerts

5156. The reaction of fluorine atoms with silicon: Daniel L Flamm et al,J Appl Phys,52 (5), 1981, 3633–3639

5156. The reaction of fluorine atoms with silicon: Daniel L Flamm et al,J Appl Phys,52 (5), 1981, 3633–3639

Infrared chemiluminescence in the reactions of atomic fluorine with ethanol, propanol-(2) and some deuterated analogs

In the reactive systems F+C 2H 5OH, F+C 2D 5OD, F+C 2H 5OD, F+(CH 3) 2CHOH, F+(CD 3) 2CHOH, and F+(CD 3) 2CDOH the infrared emission spectra were recorded from HF and/or DF in the fundamental region. Hydrogen abstraction takes place from CH and OH bonds. Vibrational relaxation was suppressed and rotational relaxation took place only to a minor extent. HF(DF) excitation reaches the thermodynamic limit within error limits in all cases. The vibrational distributions of HF for the systems F+(CD 3) 2CHOH, F+(CD 3) 2CDOH show no populati inversion. The vibrational distribution of HF for all other systems and all the DF vibrational distributions obtained show population inversion. Inform theory was used to describe the results of those reaction channels that could be studied separately because of isotopic substitution. The results are c to the systems F + methanol and deuterated analogs investigated before in our laboratory, and to the F+CH 4, F+CD 4, and F+H 2O 2 reactio

Initial vibrational and rotational energy distributions of hydrogen and deuterium fluoride formed in the reactions of atomic fluorine with hydrogen bromide and deuterium bromide

The reaction of atomic fluorine with deuterium bromide has been studied by the arrested relaxation chemiluminescence method. Further experiments involving the non-deuteriated reaction are also reported. The results confirm that the dynamics of these reactions fall into the same general category as the corresponding ones involving the other hydrogen halides. There is the usual high degree of vibrational energy level population inversion in the product hydrogen fluoride and deuterium fluoride and the mean fractions of available energy entering vibration, rotation and translation are determined as = 0·56, = 0·11, = 0·33 and = 0·61, = 0·11 and = 0·28 for the HBr and DBr reactions respectively. Trajectory calculations have been made in order to determine the LEPS surface most capable of reproducing the experimental energy distributions. Information theoretic analysis has been applied to both vibrational and rotational data to determine the extent of deviation from statistica...

The reaction of fluorine atoms with silicon

Fluorine atoms etch silicon with a rate, RF(Si) = 2.91±0.20×10−12T1/2nFe−0.108 eV/kT Å/min, where nF (cm−3) is the atom concentration. This etching is accompanied by a chemiluminescent continuum in the gas phase which exhibits the same activation energy. These phenomena are described by the kinetics: (1) F(g)+Sisurf→SiF2(g), (2) SiF2(g) +F(g) →SiF*3(g), (3) SiF2(g) +F2(g) →SiF*3(g) +F(g), (4) SiF*3(g) →SiF3(g) +hνcontinuum where formation of SiF2 is the rate-limiting step. A detailed model of silicon gasification is presented which accounts for the low atomic fluorine reaction probability (0.00168 at room temperature) and formation of SiF2 as a direct product. Previously reported etch rates of SiO2 by atomic fluorine are high by a constant factor. The etch rate of SiO2 is RF(SiO2) = (6.14±0.49)×10−13nF T1/2e−0.163/kT Å/min and the ratio of Si to SiO2 etching by F atoms is (4.74±0.49)e−0.055/kT.

Infrared chemiluminescent reactions of fluorine atoms with methanol and some deuterated analogs

In the reactive systems F + CH 3OH, F + CH 3OD, F + CD 3OD the emission spectra were recorded from HF and/or DF in the fundamental region. Fluorine atom attack occurs at the methyl and at the hydroxyl end of the alcohols. Vibrational relaxation was suppressed and rotational relaxation took place only to a minor extent. The relative populations N υ J , which are therefore proportional to relative detailed rate constants, were used to evaluate internal branching ratios and kinetic isotope effects. For the attack of the methyl group k H/ k D = 1.2 ± 0.3 and for the attack of the hydroxyl group k H/ k D = 0.6 ± 0.2 were deduced. It is concluded that HF(DF) excitation takes place up to the thermodynamical limit in all cases. < f V > ranges between 0.41 and 0.53, < f R> between 0.02 and 0.06.

The detailed isotope effect in the F + NH 3 AND F + ND 3 reactions

Arrested relaxation infrared chemiluminescence measurements show that the reaction of fluorine atoms with ND 3 channels a much larger fraction of the available exoergicity into DF product vibration than the analogous NH 3 reaction channels into HF vibration. This result is interpreted by a mechanism involving competition between direct abstraction and formation of an intermediate complex.

Matrix isolation study of the reaction of fluorine atoms with the trifluoromethyl halides, Infrared spectroscopic evidence for the CF3XF free radicals

Matrix isolation study of the reaction of fluorine atoms with the trifluoromethyl halides, Infrared spectroscopic evidence for the CF3XF free radicals

Infrared chemiluminescence investigation of the reactions of halogen atoms with deuterated ethylene and benzene derivatives

The technique of arrested relaxation infrared chemiluminescence has been used to investigate the reactions of halogen atoms with various deuterated olefinic and aromatic compounds. From infrared emission spectra of the products, the vibrational energy distributions were measured and then compared to the distributions resulting from statistical partitioning of energy. The reactions studied here are reactions of fluorine atoms with ethylene-d4, vinyl chloride-d3, vinyl bromide-d3, benzene-d6, toulene-d8, chlorobenzene-d5, and bromobenzene-d5 and the reaction of chlorine atoms with vinyl bromide-d3. Nonstatistical product energy distributions were observed for the F+ethylene-d4 and Cl+vinyl bromide-d3 reactions. All other reactions showed a statistical distribution of energy among the modes that were observed. The mechanism of distribution of energy among vibrational modes in intermediate size molecules is discussed in relation to these results.

Reaction of F atoms with dichloromethane by modulated molecular beam mass spectrometry

The reaction of atomic fluorine with dichloromethane has been studied by the diffusion cloud in a flow technique. Fluorine atoms were generated through F 2 dissociation in a high-frequency discharge. The reaction products were detected mass spectrometrically, applying the technique of focusing the paramagnetic component of the molecular beam in an inhomogeneous magnetic field to detect radical species. Cl atoms and CHCl 2 and CF 3 free radicals have been identified among the reaction products. The initial step was shown to be hydrogen atom abstraction. The room temperature rate constant of this reaction was found to be k 0 = (1.51 ± 0.28) X 10 −11 cm 3/s. The rate constant of the secondary reaction of fluorine atoms with dichloromethyl radicals, which is suggested to produce mainly HCl, was evaluated as 3 X 10 −10 cm 3/s.

The dynamics of the reactions of fluorine atoms with ammonia and hydrazine

Initial product energy distributions are reported for the reactions of fluorine atoms with hydrazine and ammonia, as measured by infrared chemiluminescence. In contrast to the reaction with hydrazole acid, neither the vibrational nor rotational energy distributions appear to be statistical. Indirect evidence is presented indicating that the NH 2 product from the reaction with ammonia is produced with some vibrational excitation.