51312-24-4Relevant articles and documents
Fraenz, H.,Kallmann, H.
, p. 924 - 950 (1925)
Temperature and pressure dependent rate coefficients for the reaction of Hg with Cl and the reaction of Cl with Cl: A pulsed laser photolysis-pulsed laser induced fluorescence Study
Donohoue, Deanna L.,Bauer, Dieter,Hynes, Anthony J.
, p. 7732 - 7741 (2005)
A pulsed laser photolysis-pulsed laser induced fluorescence technique has been employed to study the recombination of mercury and chlorine atoms, Hg + Cl + M → HgCl + M (1), and the self-reaction of chlorine atoms, Cl + Cl + M → Cl2 + M (2). Rate coefficients were determined as a function of pressure (200-600 Torr) and temperature (243-293 K) in N2 buffer gas and as a function of pressure (200-600 Torr) in He buffer gas at room temperature. For reaction (1) kinetic measurements were obtained under conditions in which either mercury or chlorine atoms were the reactant in excess concentration while simultaneously monitoring the concentration of both reactants. An Arrhenius expression of (2.2 ± 0.5) × 10 -32 exp{(680 ± 400)(1/T - 1/298)} cm6 molecule -2 s-1 was determined for the third-order recombination rate coefficient in nitrogen buffer gas. The effective second-order rate coefficient for reaction 1 under atmospheric conditions is much smaller than prior determinations using relative rate techniques. For reaction (2) we obtain an Arrhenius expression of (8.4 ± 2.3) × 10-33 exp{(850 ± 470)(1/T - 1/298)} cm6 molecule-2 s-1 for the third-order recombination rate coefficient in nitrogen buffer gas. The rate coefficients are reported with a 2σ error of precision only; however, due to the uncertainty in the determination of absolute chlorine atom concentrations we conservatively estimate an uncertainty of ±50% in the rate coefficients. For both reactions the observed pressure, temperature, and buffer gas dependencies are consistent with the expected behavior for three-body recombination.
Interpretations of the mercury halide (B 2Σ+ - X 2Σ+) chemiluminescence from reactive quenching of Hg(3P2) by halogen containing molecules
Dreiling, T. D.,Setser, D. W.
, p. 5423 - 5438 (1983)
The HgX(B 2Σ+ - X 2Σ+), X = halogen, emission spectra have been recorded from Hg(3P2) atom reactions with several halogen containing molecules using a flowing afterglow reactor.The HgX* emission intensities were compared with the HgCl* emission intensity from Hg(3P2) + Cl2 to assign rate constants for HgX(B) formation.The Hg(3P2) + diatomic halogen reactions have large k and their branching fractions for HgX(B) formation are probably unity.The polyatomic reagents generally gave much smaller k; although, a few moderately good donors, e.g., CF3I, CBr4, CCl4, and NF3 were identified.The experimental spectra were numerically simulated to assign HgX(B) vibrational energy distributions.A decrease in v(HgX)> was found for the Cl2, Br2, I2 series which is analogous to previous findings for v(XeX)> from reactive quenching of Xe(3P2).Possible reasons for the similarity are discussed.The HgX(B) vibrational energy disposal for polyatomic reagents is compared to analogous data for reactions of alkaline earth metal atoms and Xe(3P2).
A Flowing-Afterglow Study of the Quenching Reactions of Hg(3P2) and Hg(3P0) Atoms by Halogens, Interhalogens, and Polyatomic Halide Molecules
Zhang, Fu Min,Oba, D.,Setser, D. W.
, p. 1099 - 1114 (2007/10/02)
Mercury (3P2) and (3P0) metastable atoms were prepared in a flowing afterglow reactor by passing He, Ne, or Ar carrier gas containing Hg through a dc discharge.The interaction of Hg(3P2) with 30 halogen-containing molecules (325 K) was studied by observation of the HgCl, HgBr, and HgI(B2Σ+-X2Σ+) chemiluminescent spectra.Intramultiplet relaxation to Hg(3P1) also was monitored for some of these molecules plus NH3, CH4, and CF4 and five nonreactive diatomic molecules.The addition of N2 to the flow reactor removes the Hg(3P2) atoms and the reactions of Hg(3P0) can be isolated.The branching fraction for HgX(B) formation, X = Cl, Br, and I, is much lower for Hg(3P0) than for Hg(3P2) reactions.Computer simulation of the HgX(B-X) spectra provided nascent HgX(B) vibrational distributions.The reactions of Hg(3P2) with halogens, mixed halogens, and ICN resemble the analogous Xe(3P2) atom reactions with regard to product branching fractions and energy disposal.These data are discussed in terms of the covalent-ionic curve-crossing reactive quenching mechanism.Upper limits are set for the bond energies of CF3NCl-Cl, CF3NCl-Br, CF2ClNCl-Cl, CF2ClNF-Cl, CF2N-Cl, and CF2BrCF2-I from the HgX(B-X) spectra.The B- and X-state potentials of HgCl, HgBr, and HgI were improved relative to our prior work to better simulate the HgX(B-X) spectra.The excitation-transfer reaction between Hg(3P0,2) and CN was observed as a secondary reaction with BrCN and ICN.
