Subsequent Reaction of CH2(1A) with N2 Molecule as a Potentially Important Source of HCN in the Atmosphere of Titan: Studies by Quantum-Chemical and Statistical Rate Theories

IF 2.9 3区 化学 Q2 CHEMISTRY, MULTIDISCIPLINARY
Vahid Saheb*, 
{"title":"Subsequent Reaction of CH2(1A) with N2 Molecule as a Potentially Important Source of HCN in the Atmosphere of Titan: Studies by Quantum-Chemical and Statistical Rate Theories","authors":"Vahid Saheb*,&nbsp;","doi":"10.1021/acsearthspacechem.4c0021310.1021/acsearthspacechem.4c00213","DOIUrl":null,"url":null,"abstract":"<p >In this theoretical research, the possibility of the formation of the significant prebiotic hydrogen cyanide molecule and other important species in Titan’s atmosphere through the subsequent reactions of singlet methylene species, <sup>1</sup>CH<sub>2</sub>, with the N<sub>2</sub> molecule is investigated. The stationary points geometries and energies of species involved in the studied reaction are calculated by high-level quantum-chemical methods such as W1RO and CCSDT(Q) methods. Next, the rate coefficients for the formation of products are computed by sophisticated statistical rate theories including RRKM and VRC-TST. It is inferred from a previous theoretical study that CH<sub>2</sub>NN is produced predominantly from the reaction of <sup>1</sup>CH<sub>2</sub> with N<sub>2</sub> in the atmosphere of Titan [<contrib-group><span>Xu, S.</span>; <span>Lin, M. C.</span></contrib-group> <cite><i>J. Phys. Chem. A</i></cite> <span>2010</span>, <em>114</em>, 5195–5204]. The reactive CH<sub>2</sub>NN molecules react with other atmospheric species like <sup>1</sup>CH<sub>2</sub> to produce new species. According to the present study, <sup>1</sup>CH<sub>2</sub> species add to CH<sub>2</sub>NN molecules through relatively fast barrierless processes to produce some chemically activated intermediates. These intermediates rapidly decompose to yield 2 NCH<sub>2</sub>, HCN + CH<sub>2</sub>NH, and C<sub>2</sub>H<sub>4</sub> + N<sub>2</sub> products. The calculated data reveal that HCN and C<sub>2</sub>H<sub>4</sub> are efficiently produced from the subsequent reaction of <sup>1</sup>CH<sub>2</sub> with N<sub>2</sub> molecules in the atmosphere of Titan. The following rate constant expressions are suggested for the computed rate coefficients for the production of 2 NCH<sub>2</sub> (<i>k</i><sub>1</sub>), HCN + CH<sub>2</sub>NH (<i>k</i><sub>2</sub>), and C<sub>2</sub>H<sub>4</sub> + N<sub>2</sub> (<i>k</i><sub>3</sub>) from <sup>1</sup>CH<sub>2</sub> + CH<sub>2</sub>NN reaction over the temperature range 200–700 K: <i>k</i><sub>1</sub> = 5.48 × 10<sup>–10</sup> (T/300)<sup>0.258</sup> exp (255/T) <i>k</i><sub>2</sub> = 1.15 × 10<sup>–14</sup> (T/300)<sup>0.901</sup> exp (355/T) <i>k</i><sub>3</sub> = 3.10 × 10<sup>–10</sup> (T/300)<sup>−0.428</sup> exp (130/T).</p>","PeriodicalId":15,"journal":{"name":"ACS Earth and Space Chemistry","volume":"8 12","pages":"2474–2482 2474–2482"},"PeriodicalIF":2.9000,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"ACS Earth and Space Chemistry","FirstCategoryId":"92","ListUrlMain":"https://pubs.acs.org/doi/10.1021/acsearthspacechem.4c00213","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0

Abstract

In this theoretical research, the possibility of the formation of the significant prebiotic hydrogen cyanide molecule and other important species in Titan’s atmosphere through the subsequent reactions of singlet methylene species, 1CH2, with the N2 molecule is investigated. The stationary points geometries and energies of species involved in the studied reaction are calculated by high-level quantum-chemical methods such as W1RO and CCSDT(Q) methods. Next, the rate coefficients for the formation of products are computed by sophisticated statistical rate theories including RRKM and VRC-TST. It is inferred from a previous theoretical study that CH2NN is produced predominantly from the reaction of 1CH2 with N2 in the atmosphere of Titan [Xu, S.; Lin, M. C. J. Phys. Chem. A 2010, 114, 5195–5204]. The reactive CH2NN molecules react with other atmospheric species like 1CH2 to produce new species. According to the present study, 1CH2 species add to CH2NN molecules through relatively fast barrierless processes to produce some chemically activated intermediates. These intermediates rapidly decompose to yield 2 NCH2, HCN + CH2NH, and C2H4 + N2 products. The calculated data reveal that HCN and C2H4 are efficiently produced from the subsequent reaction of 1CH2 with N2 molecules in the atmosphere of Titan. The following rate constant expressions are suggested for the computed rate coefficients for the production of 2 NCH2 (k1), HCN + CH2NH (k2), and C2H4 + N2 (k3) from 1CH2 + CH2NN reaction over the temperature range 200–700 K: k1 = 5.48 × 10–10 (T/300)0.258 exp (255/T) k2 = 1.15 × 10–14 (T/300)0.901 exp (355/T) k3 = 3.10 × 10–10 (T/300)−0.428 exp (130/T).

Abstract Image

求助全文
约1分钟内获得全文 求助全文
来源期刊
ACS Earth and Space Chemistry
ACS Earth and Space Chemistry Earth and Planetary Sciences-Geochemistry and Petrology
CiteScore
5.30
自引率
11.80%
发文量
249
期刊介绍: The scope of ACS Earth and Space Chemistry includes the application of analytical, experimental and theoretical chemistry to investigate research questions relevant to the Earth and Space. The journal encompasses the highly interdisciplinary nature of research in this area, while emphasizing chemistry and chemical research tools as the unifying theme. The journal publishes broadly in the domains of high- and low-temperature geochemistry, atmospheric chemistry, marine chemistry, planetary chemistry, astrochemistry, and analytical geochemistry. ACS Earth and Space Chemistry publishes Articles, Letters, Reviews, and Features to provide flexible formats to readily communicate all aspects of research in these fields.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信