ESR‐spektroskopische Untersuchung der Reaktion von atomarem Wasserstoff mit H<sub>2</sub>S

Mihelcic, D.; Schindler, R. N.

doi:10.1002/bbpc.19700741213

Cited by 30 publications

(8 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Figure shows the calculated initial state-specific rate constants in the temperature range from 100 to 2500 K of the title reaction, together with the results on the PIP-NN PES and some experimental thermal rate constants. − Note that the rate constants of the (100) and (001) states have been multiplied by the Boltzmann factor e – E v0 / k b T . As seen, the ground state rate constants show non-Arrhenius behavior at low temperatures, which is consistent with the experimental results.…”

Section: Resultsmentioning

confidence: 99%

“…Initial ground, (100), and (001) state-specific rate constants of the title reaction, together with the ground state rate constants on the PIP-NN PES, and the experimental thermal rate constants from refs − and …”

Section: Resultsmentioning

confidence: 99%

“…The H + H 2 S reaction is important for both combustion and interstellar ice chemistry because H 2 S is a common impurity known to substantially alter the combustion properties of fuels − and proposed as a contributing factor to sulfur depletion in the gas phase in the dense (dark) regions. − Several experiments have measured rate constants for the hydrogen abstract channel and revealed a non-Arrhenius temperature dependence, which has been ascribed to the quantum tunneling effect, as explained by transition-state theory with tunneling correction. − …”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Differential Cross Sections for the H + H₂S → H₂ + SH Reaction: A Full-Dimensional State-to-State Quantum Dynamics Study

Xu,

Chen,

Liu

et al. 2023

J. Phys. Chem. A

View full text Add to dashboard Cite

We utilized the time-dependent wave packet approach to compute the first full-dimensional (6D) state-to-state differential cross sections (DCSs) for the title reaction with the initial nonrotating H2S in the ground and the (100) and (001) vibrational excited states. It is found that the fundamental symmetric and asymmetric stretching excitations of H2S exhibit almost the same influence on the DCS, but unlike the H + H2O → H2 + OH reaction, they greatly increase the vibrational excitation of both the H2 and SH products. The hot vibrational state distributions of H2 are consistent with the prediction of product energy disposal by Polanyi’s rules for an early barrier reaction. Because the incident H atom reacts strongly with both the ground and excited S–H states, the large populations of product SH(v 2 = 1), which are very close to the relative reactivity of the initial S–H(v = 0) state, can still be explained by the local mode picture for H2S and the nonreacting SH bond’s spectator nature.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Differential Cross Sections for the H + H₂S → H₂ + SH Reaction: A Full-Dimensional State-to-State Quantum Dynamics Study

Xu,

Chen,

Liu

et al. 2023

J. Phys. Chem. A

View full text Add to dashboard Cite

show abstract

“…The first temperature-dependent measurement of the rate constant for reaction (1) was conducted by Mihelcic and Schindler [5], who used a discharge flow system combined with ESR detection of hydrogen atoms. The most reliable measurements of k 1 at room temperature [8,[10][11][12] (not shown in Figure 5 for clarity) are in good agreement with each other.…”

Section: Comparison With Previous Datamentioning

confidence: 99%

“…The temperature dependence of the rate constant of reaction (1), which proceeds through the abstraction of a hydrogen atom, is also of theoretical interest, in particular for assessing the effect of quantum tunneling [2,3]. Reaction (1) has been intensively studied over the past few decades, both experimentally [4][5][6][7][8][9][10][11][12][13][14][15] and theoretically [2,3,13,15,16]. Although there is now some experimental and theoretical evidence for the curvature of the Arrhenius plot for reaction (1), it has never actually been observed experimentally in any single study conducted over a sufficiently wide temperature range.…”

Section: Introductionmentioning

confidence: 99%

Temperature-Dependent Kinetic Study of the Reactions of Hydrogen Atoms with H2S and C2H4S

Bedjanian

2023

Molecules

View full text Add to dashboard Cite

A discharge-flow reactor combined with modulated molecular beam mass spectrometry technique was employed to determine the rate constants of H-atom reactions with hydrogen sulfide and thiirane. The rate constants for both reactions were determined at a total pressure of 2 Torr from 220 to 950 K under pseudo-first-order conditions by monitoring either consumption of H atoms in excess of H2S (C4H4S) or the molecular species in excess of atomic hydrogen. For H + H2S reaction, a suggested previously strong curvature of the Arrhenius plot was confirmed: kl = 8.7 × 10−13 × (T/298)2.87 × exp(−125/T) cm3 molecule−1 s−1 with a conservative uncertainty of 15% at all temperatures. Non-Arrhenius behavior was also observed for the reaction of H-atom with C2H4S, with the experimental rate constant data being best fitted to a sum of two exponential functions: k2 = 1.85 × 10−10 exp(−1410/T) + 4.17 × 10−12 exp(−242/T) cm3 molecule−1 s−1 with an independent of temperature uncertainty of 15%.

show abstract

Studies on the oxidation mechanism of H2S based on direct examination of the key reactions

Tsuchiya

Kamiya

Matsui

1997

Int. J. Chem. Kinet.

View full text Add to dashboard Cite

numbers of studies were performed until very recently on the fundamental oxidation reaction mechanism of hydrogen sulfide and related H 9 S 9 O reaction systems.The oxidation process of H 2 S (and some times the catalytic effect of SO 2 ) have been investigated in several flame studies [1 -5], and the reaction mechanisms were discussed based on the measured product distributions. These studies have provided much useful information on the elementary reactions of H 9 S 9 O systems, however, it is generally very difficult to judge the reliability of kinetic/thermodynamic parameters of individual elementary reactions proposed in these indirect studies. It is also noted that even a conventional shock tube study was not performed for clarifying oxidation mechanism of H 2 S (as far as we know), except an ignition delay mea- INTRODUCTIONThe oxidation of hydrogen sulfide in combustion of fossil fuels and the consecutive atmospheric processes of sulfur oxides are creating serious pollution problems on a global scale.Many practical studies for reducing SO x in combustion systems have been conducted from the engineering point of view. In contrast, only very limited (1), the rate constants evaluated by numerical simulations are summarized as; k 1 ϭ 3.1 ϫ 10 Ϫ11 exp[Ϫ 75 kJ mol Ϫ1 /RT ] cm 3 molecule Ϫ1 s Ϫ1 (T ϭ 1400 -1850 K) with an uncertainty factor of about 2. Direct measurements of the rate constants for S ϩ O2 : SO ϩ O (2), and SO ϩ O 2 : SO 2 ϩ O (3) yield k 2 ϭ (2.5 Ϯ 0.6) ϫ 10 Ϫ11 exp[Ϫ(15.3 Ϯ 2.5) kJ mol Ϫ1 /RT ] cm 3 molecule Ϫ1 s Ϫ1 (T ϭ 980 -1610 K) and, k 3 ϭ (1.7 Ϯ 0.9) ϫ 10 Ϫ12 exp[Ϫ(34 Ϯ 11) kJ mol Ϫ1 /RT ] cm 3 molecule Ϫ1 s Ϫ1 (T ϭ 1130 -1640 K), respectively. By summarizing these data together with the recent experimental results on the H 9 S 9 O reaction systems, a new kinetic model for the H 2 S oxidation process is constructed. It is found that this simple reaction scheme is consistent with the experimental result on the induction time of SO 2 formation obtained by Bradley and Dobson.

show abstract

ESR‐spektroskopische Untersuchung der Reaktion von atomarem Wasserstoff mit H₂S

Cited by 30 publications

References 30 publications

Differential Cross Sections for the H + H₂S → H₂ + SH Reaction: A Full-Dimensional State-to-State Quantum Dynamics Study

Differential Cross Sections for the H + H₂S → H₂ + SH Reaction: A Full-Dimensional State-to-State Quantum Dynamics Study

Temperature-Dependent Kinetic Study of the Reactions of Hydrogen Atoms with H2S and C2H4S

Studies on the oxidation mechanism of H2S based on direct examination of the key reactions

Contact Info

Product

Resources

About

ESR‐spektroskopische Untersuchung der Reaktion von atomarem Wasserstoff mit H2S

Cited by 30 publications

References 30 publications

Differential Cross Sections for the H + H2S → H2 + SH Reaction: A Full-Dimensional State-to-State Quantum Dynamics Study

Differential Cross Sections for the H + H2S → H2 + SH Reaction: A Full-Dimensional State-to-State Quantum Dynamics Study

Temperature-Dependent Kinetic Study of the Reactions of Hydrogen Atoms with H2S and C2H4S

Studies on the oxidation mechanism of H2S based on direct examination of the key reactions

Contact Info

Product

Resources

About

ESR‐spektroskopische Untersuchung der Reaktion von atomarem Wasserstoff mit H₂S

Differential Cross Sections for the H + H₂S → H₂ + SH Reaction: A Full-Dimensional State-to-State Quantum Dynamics Study

Differential Cross Sections for the H + H₂S → H₂ + SH Reaction: A Full-Dimensional State-to-State Quantum Dynamics Study