Reaction Dynamics of O(P-3) + Propyne: I. Primary Products, Branching Ratios, and Role of Intersystem Crossing from Crossed Molecular Beam Experiments

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989100%3A27200%2F16%3A86099685" target="_blank" >RIV/61989100:27200/16:86099685 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1021/acs.jpca.6b01563" target="_blank" >http://dx.doi.org/10.1021/acs.jpca.6b01563</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/acs.jpca.6b01563" target="_blank" >10.1021/acs.jpca.6b01563</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Reaction Dynamics of O(P-3) + Propyne: I. Primary Products, Branching Ratios, and Role of Intersystem Crossing from Crossed Molecular Beam Experiments

Popis výsledku v původním jazyce

We performed synergic experimental/theoretical studies on the mechanism of the O(P-3) + propyne reaction by combining crossed molecular beams experiments with mass-spectrometric detection and time-of-flight analysis at 9.2 kcal/mol collision energy (E-c) with ab initio electronic structure calculations at a high level of theory of the relevant triplet and singlet potential energy surfaces (PESs) and statistical calculations of branching ratios (BRs) taking into account intersystem crossing (ISC). In this paper (I) we report the results of the experimental investigation, while the accompanying paper (II) shows results of the theoretical investigation with comparison to experimental results. By exploiting soft electron ionization detection to suppress/mitigate the effects of the dissociative ionization of reactants, products, and background gases, product angular and velocity distributions at different charge-to-mass ratios were measured. From the laboratory data angular and translational energy distributions in the center-of-mass system were obtained for the five competing most important product channels, and product BRs were derived. The reactive interaction of O(P-3) with propyne under single collision conditions is mainly leading to the rupture of the three-carbon atom chain, with production of the radical products methylketenyl + atomic hydrogen (BR = 0.04), methyl + ketenyl (BR = 0.10), and vinyl + formyl (BR = 0.11) and the molecular products ethylidene/ethylene + carbon monoxide (BR = 0.74) and propandienal + molecular hydrogen (BR = 0.01). Because some of the products can only be formed via ISC from the entrance triplet to the low-lying singlet PES, we infer from their BRs an amount of ISC larger than 80%. This value is dramatically large when compared to the negligible ISC reported for the O(P-3) reaction with the simplest alkyne, acetylene.

Název v anglickém jazyce

Reaction Dynamics of O(P-3) + Propyne: I. Primary Products, Branching Ratios, and Role of Intersystem Crossing from Crossed Molecular Beam Experiments

Popis výsledku anglicky

We performed synergic experimental/theoretical studies on the mechanism of the O(P-3) + propyne reaction by combining crossed molecular beams experiments with mass-spectrometric detection and time-of-flight analysis at 9.2 kcal/mol collision energy (E-c) with ab initio electronic structure calculations at a high level of theory of the relevant triplet and singlet potential energy surfaces (PESs) and statistical calculations of branching ratios (BRs) taking into account intersystem crossing (ISC). In this paper (I) we report the results of the experimental investigation, while the accompanying paper (II) shows results of the theoretical investigation with comparison to experimental results. By exploiting soft electron ionization detection to suppress/mitigate the effects of the dissociative ionization of reactants, products, and background gases, product angular and velocity distributions at different charge-to-mass ratios were measured. From the laboratory data angular and translational energy distributions in the center-of-mass system were obtained for the five competing most important product channels, and product BRs were derived. The reactive interaction of O(P-3) with propyne under single collision conditions is mainly leading to the rupture of the three-carbon atom chain, with production of the radical products methylketenyl + atomic hydrogen (BR = 0.04), methyl + ketenyl (BR = 0.10), and vinyl + formyl (BR = 0.11) and the molecular products ethylidene/ethylene + carbon monoxide (BR = 0.74) and propandienal + molecular hydrogen (BR = 0.01). Because some of the products can only be formed via ISC from the entrance triplet to the low-lying singlet PES, we infer from their BRs an amount of ISC larger than 80%. This value is dramatically large when compared to the negligible ISC reported for the O(P-3) reaction with the simplest alkyne, acetylene.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

CF - Fyzikální chemie a teoretická chemie

OECD FORD obor

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Projekt

<a href="/cs/project/LD11012" target="_blank" >LD11012: Kombinované modely chemické kinetiky a fluidní dynamiky pro simulace procesů čistšího spalování</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of Physical Chemistry A

ISSN

1089-5639

e-ISSN

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Svazek periodika

120

Číslo periodika v rámci svazku

27

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

16

Strana od-do

4603-4618

Kód UT WoS článku

000379988900003

EID výsledku v databázi Scopus

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