13863-41-7Relevant articles and documents
Formation of Gas-Phase Bromine Compounds by Reaction of Solid NaBr with Gaseous ClONO2, Cl2, and BrCl at 298 K
Berko, H. N.,McCaslin, P. C.,Finlayson-Pitts, B. J.
, p. 6951 - 6958 (1991)
The reactions at 298 K of solid NaBr with ClONO2(g), Cl2(g), and BrCl(g) at concentrations of (0.9-19.4) x 1013 molecules cm-3 as mixtures in He flowing over the salt were investigated.The gaseous products, analyzed by mass spectrometry, were as follows: for the ClONO2 reaction, Br2 initially and subsequently BrCl and Cl2; for the Cl2 reaction, Br2 followed by BrCl; and for the BrCl reaction, Br2.Ion chromatographic analysis did not show significant replacement of bromide by chloride or nitrate in the bulk solid NaBr.Nitrate formation, however, was verified by FTIR in the ClONO2-NaBr reaction.Surface analyses of the reacted NaBr salts were carried out using X-ray photoelectron spectroscopy.Detectable amounts of surface products (>50percent monolayer coverage for chloride) could be seen only when NaBr was exposed to high concentration of Cl2 for days in a static system.Mechanisms of formation of the gaseous products in these reactions are hypothesized.The potential role of the ClONO2-NaBr reaction in converting both the bromide ion in NaBr and the chlorine atom in ClONO2 into highly photochemically labile gaseous compounds in the troposphere and stratosphere is discussed.
Bromine Monofluoride
Drews, Thomas,Seppelt, Konrad
, p. 2106 - 2110 (2012)
BrF can be prepared by reaction of Br2 and F2 in various solvents below -100 °C. In solution it is identified by 19F NMR and Raman spectroscopy. From CH3Cl solution a single crystal structure determination of a BrF/CH3Cl adduct was obtained. The preparationfrom BrF3 and Br2 at 600 °C also delivers BrF in small amounts. The crystal structure of BrCl comes in an ordered and a disordered variety. The ordered structure is made of Br- Cl···Br-Cl chains. Computations suggest that neat BrF crystallizes in a dipol-dipole type polymeric structure rather than a halogen bonded one as in ClF. A possible intermediate along the decomposition pathway into BrF3 and Br2 is Br- BrF2.
The geometry and intermolecular binding of HCN...BrCl probed by rotational spectroscopy
Hinds, K.,Legon, A. C.
, p. 467 - 473 (1995)
Ground-state rotational spectra of several isotopomers of a linear complex formed between HCN and BrCl were observed by pulsed-nozzle, F-T microwave spectroscopy and analysed to give the spectroscopic constants B(0), D(J), χ(Br), χ(Cl), and M(bb)(Br). The order HCN...BrCl of thenuclei was established from the changes in the B(0) values on isotopic substitution. The small fractional electronic charge (.delta~0.05) transferred from Br to Cl on complex formation and the intermolecularstretching force constant (k(σ)~11 N m**-1) estimated from the spectroscopic constants indicates a weak interaction of HCN and BrCl, with little perturbation of the charge distribution of BrCl.
Laser initiated chain reactions: A generalized extension to complex chemical chain systems
Nesbitt, David J.,Leone, Stephen R.
, p. 4949 - 4959 (1981)
We present a generalized extension of the detailed kinetic and experimental analysis for studying rapid gas phase chemical chain reactions initiated by short pulse laser photolysis.The key ingredients of the technique are pulsed laser initiation of the chain by dissociation of a small fraction of a precursor molecule to produce radicals (Cl2 Cl + Cl), followed by time resolved, infrared chemiluminescence detection of product HCl(v) emission from the propagation steps (Cl radical + RH R radical + HC(v), R + Cl2 Cl radical + RCl). This laser initiated chain reaction technique is now extended to encompass a far wider range of chain kinetic rates, mechanisms, and product state distributions.Three prototypical systems are investigated which demonstrate distinctly different facets of the extended technique: (1) Cl2/HBr - a slow chain reaction system, (2) Cl2/CH3SH - a multiple chain reaction system, and (3) Cl2/H2 - a slow starting chain reaction system in which the product emission appears after an intital induction period.Quantitative rate data are obtained for several chain propagation steps: Br radical + Cl2 -> Cl radical + BrCl, k = 2.4(+/-0.2)x10-15 cm3 molecule -1 s-1; Cl radical + CH3SH -> radical CH2SH + HCl(v), k = 4.3(+/-1)x10-12 cm3 molecule-1 s-1; radical CH2SH + Cl2 -> Cl radical + ClCH2SH, k = 2.6(+/-1)x10-13 cm3 molecule -1 s-1. The results illuminate a more general approach to precise kinetic and mechanistic studies of complex chain reactions under nearly ideal psuedo-first-order laboratory conditions.
Experimental verification of gas phase bromine enrichment in reactions of HOBr with sea salt doped ice surfaces
Kirchner,Benter, Th,Schindler
, p. 975 - 977 (1997)
Significant gas phase bromine enrichment is experimentally verified on flowing gaseous HOBr over ice surfaces doped with sodium halides of sea salt composition. It is argued that formation of Br2Cl- in the condensed phase followed by
Heterogeneous Reaction HOCl + HBr → BrCl + H2O on Ice Films
Chu, Liang,Chu, Liang T.
, p. 691 - 699 (1999)
The heterogeneous reaction HOCl + HBr(s) → BrCl + H2O(s) on the ice surface at 189 and 220 K has been investigated in a flow reactor interfaced with a differentially pumped quadrupole mass spectrometer. Pseudo first-order decay of HOCl over the HBr-treated ice surfaces has been determined under the condition of PHOCI HBr. For the HBr partial pressure in the range of 1.1 × 10-7 to 6.6 × 10-5 Torr, the reaction probability (yg) was determined in the range of 0.06 to 0.38 at 189 K. The reaction probability is in the range of 0.01 to 0.07 at 220 K for HBr partial pressure from 7.2 × 10-7 to 1.3 × 10-5 Torr. The reaction probability was found to be strongly dependent on the ice surface temperature. The reaction probability is higher at the lower temperature than that at the warmer temperature and a mechanistic explanation is provided. The true reaction probabilities (yt) of the reaction were calculated using a pore diffusion model. The kinetic analysis indicates that the heterogeneous reaction of HOCl + HBr may follow the Eley-Rideal type of mechanism. Also, the heat of uptake of HOCl on ice was determined to be about -8.5 ± 2 kcal/mol.
Vacuum-Ultraviolet Absorption, Fluorescence Excitation, and Dispersed Fluorescence Spectra of BrCl
Hopkirk, Andrew,Shaw, David,Donovan, Robert J.,Lawley, Kenneth P.,Yencha, Andrew J.
, p. 7338 - 7342 (1989)
Absorption and fluorescence excitation spectra of BrCl have been recorded between 137 and 180 nm with the use of synchrotron radiation.A pronounced resonance structure has been observed in the fluorescence excitation spectrum and it is attributed to coupling of ion-pair and Rydberg states.Dispersed fluorescence spectra have been obtained through vacuum-ultraviolet (vacuum-UV) excitation that display several oscillatory continua.These are assigned to emission predominantly from the lowest Ω = O+ ion-pair state (the E state) with probably some contribution from the f(O+) state of the second cluster.Fluorescence to four of the five O+ states correlating with the separated atomic J = 3/2 and 1/2 states is postulated.
Precise equilibrium constants from spectrophotometric data: BrCl in Br2/Cl2 gas mixtures
Tellinghuisen, Joel
, p. 753 - 757 (2003)
The equilibrium constant for the reaction, Br2(g) + Cl2(g), ? BrCl(g). is estimated using the classic spectrophotometric method with precise data and a multispectrum fitting approach. Analysis of spectra for 18 Cl2:Br2 mixing ratios yields K° = 9/1 at 22°C, with a nominal statistical error (1 σ) of 0.04. This error translates into a remarkable precision of 0.4 cm-1 in the dissociation energy of BrCl, easily beating that for the current best spectroscopic estimate (±5 cm-1). However, a sensitivity analysis shows that K° is susceptible to small systematic errors and minor changes in the least-squares fit model, leading to a more conservative estimate of 2% error. The derived K° is consistent with statistical mechanical estimates that employ the current value for the BrCl dissociation energy, but it differs considerably from some recently measured and used values, which range from 6.4 to 10.4. The revised estimate of the BrCl dissociation energy is De = 18 248 ± 2 cm-1.
The Bromine-Chlorine Interhalides [Br3Cl5]2–, [Br4Cl4]2– and [Br6.56Cl1.44]2–
Abdelbassit, Mohammed S.,Curnow, Owen J.,Brooke, Samuel J.,Waterland, Mark R.
, p. 3302 - 3310 (2020)
The bromine-chlorine dianionic octahalide-containing salts [C3(NEt2)3]2[Br4Cl4] (1c) and [C3(NEt2)3]2[Br3Cl5] (2d) were prepared using the triaminocyclopropenium cation as a template. The salt 1c was prepared in two steps, firstly, either by addition of BrCl to the triaminocyclopropenium chloride salt [C3(NEt2)3]Cl or addition of Cl2 to the bromide salt [C3(NEt2)3]Br to form the trihalide [BrCl2]– salt, secondly, addition of half an equivalent of Br2 gave the desired product upon crystallization at low temperature. Salt 2d is prepared by addition of excess BrCl to [C3(NEt2)3]Cl. Both salts are best described as two trihalides bridged by a dihalogen. When the tetraethylammonium cation is used, a salt of the formula [NEt4]2[Br4.56Cl0.44][ClBr2] (4), containing disordered [ClBr2]– and a chain of [ClBr4]– and [Br5]– pentahalides (in a ratio of 0.44 to 0.56, respectively). These interhalides were characterized by X-ray crystallography, computational studies, Raman and Far-IR spectroscopy, as well as by TGA and melting point.
PREPARATION OF DECAHALODIPHENYL OXIDE
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Page/Page column 11, (2008/06/13)
This invention provides a process of preparing reaction-derived decahalodiphenyl oxide of high purity. The process comprises cofeeding separate feeds of (a) diphenyl oxide and/or partially brominated diphenyl oxide and (b) bromine chloride, bromine chloride and bromine, or bromine chloride and chlorine to a refluxing reaction mixture comprising bromine and at least one Lewis acid bromination catalyst so that high purity decahalodiphenyl oxide is formed.
