Effect of (H2O)n (n = 1–3) clusters on H2O2 + HO → HO2 + H2O reaction in tropospheric conditions: competition between one-step and stepwise routes

Liu

Phys. Chem. Chem. Phys.

et al. 2022

Section: Resultssupporting

confidence: 82%

The effect of (H₂O)_n (n = 1–3) clusters on the reaction of HONO with HCl: a mechanistic and kinetic study

Liu

Phys. Chem. Chem. Phys.

et al. 2022

Plasma Sources Sci. Technol.

“…H 2 O 2 can react with radicals such as OH, O( 3 P), O, and H and generate HOO, whereas the reverse reactions are negligibly slow. Moreover, the reaction of H 2 O 2 + OH can be further catalyzed in water due to the formation of H 2 O 2 •H 2 O n (n = 1-3) by a factor of 8 [54]. Although the recombination reaction of HOO to form H 2 O 2 has a comparable rate, this pathway decreases the overall concentration of H 2 O 2 by half.…”

Section: Ltp In Contact With H 2 O 2 Solutionsmentioning

confidence: 99%

Brewster angle-cavity ringdown spectroscopy for low temperature plasma measurements in multiphases

Wang

2023

We report on the development of a Brewster angle-cavity ringdown spectroscopy (BA-CRDS) system for low temperature plasma diagnostics. The system can measure gas species in solutions, with a detection limit (minimum detectable absorbance) of 9.1×10-5, which is equivalent to a detection limit of 0.04 parts per billion for measuring OH radicals in water at 308 nm. With higher reflectivity ringdown mirrors and improved designs of a Brewster angle cell, the detection limit can be potentially up to 10-6 or lower. In this exploratory study, absorption cross sections of HgBr2 and H2O2 in aqueous phase at 256 nm are measured to be (1.8±0.1)×10-18 cm2 and (5.2±0.5)×10-20 cm2, respectively. Furthermore, temporal profiles of absorbance from distilled water, HgBr2, and H2O2 solutions when interacting with a helium atmospheric plasma jet are individually characterized at different plasma powers, gas flow rates, and/or solute concentrations. The observed linear temporal profiles of absorbance from the plasma-interacted water suggest formation of H2O2 from plasma-generated OH radicals, while the nonlinear temporal profiles from the plasma-treated HgBr2 solutions reveal possible removal of HgBr2 by OH radicals. Our result demonstrates that the new BA-CRDS system is a powerful tool for quantification of reactive plasma species in multiphases or other complex settings.

“…In the atmosphere, water can exist in various forms, like cloud droplets, liquid aerosols, water clusters, and so forth. − Naturally, one cannot imagine the atmospheric chemistry without considering the role of water in the atmospheric chemical reactions. Consequently, several experimental as well as theoretical research groups have put lots of effort into investigating the effect of water on the atmospherically important chemical reactions. − In most of these studies, the water has been treated as a gaseous molecule, that is, monomer, dimer, trimer, and so forth. − ,, Only recently, some of the works have considered the surface of a water droplet as a platform to ensue a chemical reaction. ,,− Although it is known since long that the water droplets may play a crucial role in atmospheric chemistry, slow progress in experimental and theoretical work can be attributed to the lack of appropriate tools. Although the advent of some modern spectroscopic tools, like second-harmonic generation, X-ray photoelectron spectroscopy, and so forth, helps in circumventing the technical bottleneck of experimental studies, it is still challenging to study the high reactive systems on the air–water interface experimentally.…”

Section: Introductionmentioning

confidence: 99%

OH^• + HCl Reaction at the Surface of a Water Droplet: An Ab Initio Molecular Dynamical Study

Mallick

Kumar

2020

J. Phys. Chem. B

The Born–Oppenheimer molecular dynamics (BOMD) simulation has been performed to investigate the dynamics of the OH• + HCl reaction at the surface of a water droplet. The investigation suggests that the reaction occurred at the surface of the water droplet becomes almost 10 times faster than the corresponding gas-phase reaction. Besides, we have also performed the quantum mechanics/molecular mechanics calculation to calculate the unimolecular energy barrier of the reaction. The results indicate that the barrier height gets decreased by ∼0.3 kcal mol–1 at the surface of the water droplet, which also justifies the rate enhancement suggested by the BOMD simulation. The BOMD simulation also indicates that, at equilibrium, the product Cl• forms four hydrogen bonds with four interfacial water molecules, which stabilize the Cl• and resist it to escape from the surface.