Qinghui Wei, Yang Chen, Lidan Xiao, F. Boris Minaev, Hans Ågren, Bing Yan
{"title":"硫化镁(MgS)分子的辐射结合","authors":"Qinghui Wei, Yang Chen, Lidan Xiao, F. Boris Minaev, Hans Ågren, Bing Yan","doi":"10.1051/0004-6361/202452981","DOIUrl":null,"url":null,"abstract":"Addressing the formation for MgS, a relevant astrophysical problem for carbon rich stars, we have employed quantum mechanical ab initio calculations to predict the radiative association cross section and association rate coefficient of magnesium and sulfur atoms forming the magnesium sulfide molecule. This was accomplished by accounting for the emissive 1<sup>1<sup/>Π → X<sup>1<sup/>Σ<sup>+<sup/>, 1<sup>1<sup/>Δ → 1<sup>1<sup/>Π, and 1<sup>3<sup/>Σ<sup>−<sup/> →a<sup>3<sup/>Π transitions that make significant contributions to the radiative association process. The atomic ground state, Mg(<sup>1<sup/>S), and the metastable excited state, S(<sup>1<sup/>D), represent the lowest singlet dissociation limit common for the studied radiative association channels, whereas the ground states Mg(<sup>1<sup/>S) and S(<sup>3<sup/>P) represent the lowest triplet dissociation limit for these channels. The computational results show that in the temperature range of 10-10 000 K, the 1<sup>1<sup/>Π → X<sup>1<sup/>Σ<sup>+<sup/> transition dominates the formation of MgS through radiative association in the collision of Mg(<sup>1<sup/>S) and S(<sup>1<sup/>D) atoms, while the 1<sup>1<sup/>Δ → 1<sup>1<sup/>Π transition plays an important role at higher temperatures. The total rate coefficient for the singlet-singlet transitions ranges from 3.78 × 10<sup>−18<sup/> cm<sup>3<sup/> s<sup>−1<sup/> to 4.79 × 10<sup>−17<sup/> cm<sup>3<sup/> s<sup>−1<sup/>, while that for the triplet-triplet transition ranges from 2.02 × 10<sup>−22<sup/> cm<sup>3<sup/> s<sup>−1<sup/> to 6.79 × 10<sup>−18<sup/> cm<sup>3<sup/> s<sup>−1<sup/>. These total rate coefficients were fit using the three-parameter fit Arrhenius-Kooij function, which is expected to be helpful for the celestial modeling.","PeriodicalId":8571,"journal":{"name":"Astronomy & Astrophysics","volume":"53 1","pages":""},"PeriodicalIF":5.8000,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Radiative association of the magnesium sulfide (MgS) molecule\",\"authors\":\"Qinghui Wei, Yang Chen, Lidan Xiao, F. Boris Minaev, Hans Ågren, Bing Yan\",\"doi\":\"10.1051/0004-6361/202452981\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Addressing the formation for MgS, a relevant astrophysical problem for carbon rich stars, we have employed quantum mechanical ab initio calculations to predict the radiative association cross section and association rate coefficient of magnesium and sulfur atoms forming the magnesium sulfide molecule. This was accomplished by accounting for the emissive 1<sup>1<sup/>Π → X<sup>1<sup/>Σ<sup>+<sup/>, 1<sup>1<sup/>Δ → 1<sup>1<sup/>Π, and 1<sup>3<sup/>Σ<sup>−<sup/> →a<sup>3<sup/>Π transitions that make significant contributions to the radiative association process. The atomic ground state, Mg(<sup>1<sup/>S), and the metastable excited state, S(<sup>1<sup/>D), represent the lowest singlet dissociation limit common for the studied radiative association channels, whereas the ground states Mg(<sup>1<sup/>S) and S(<sup>3<sup/>P) represent the lowest triplet dissociation limit for these channels. The computational results show that in the temperature range of 10-10 000 K, the 1<sup>1<sup/>Π → X<sup>1<sup/>Σ<sup>+<sup/> transition dominates the formation of MgS through radiative association in the collision of Mg(<sup>1<sup/>S) and S(<sup>1<sup/>D) atoms, while the 1<sup>1<sup/>Δ → 1<sup>1<sup/>Π transition plays an important role at higher temperatures. The total rate coefficient for the singlet-singlet transitions ranges from 3.78 × 10<sup>−18<sup/> cm<sup>3<sup/> s<sup>−1<sup/> to 4.79 × 10<sup>−17<sup/> cm<sup>3<sup/> s<sup>−1<sup/>, while that for the triplet-triplet transition ranges from 2.02 × 10<sup>−22<sup/> cm<sup>3<sup/> s<sup>−1<sup/> to 6.79 × 10<sup>−18<sup/> cm<sup>3<sup/> s<sup>−1<sup/>. These total rate coefficients were fit using the three-parameter fit Arrhenius-Kooij function, which is expected to be helpful for the celestial modeling.\",\"PeriodicalId\":8571,\"journal\":{\"name\":\"Astronomy & Astrophysics\",\"volume\":\"53 1\",\"pages\":\"\"},\"PeriodicalIF\":5.8000,\"publicationDate\":\"2025-07-16\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Astronomy & Astrophysics\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://doi.org/10.1051/0004-6361/202452981\",\"RegionNum\":2,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"ASTRONOMY & ASTROPHYSICS\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Astronomy & Astrophysics","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1051/0004-6361/202452981","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
Radiative association of the magnesium sulfide (MgS) molecule
Addressing the formation for MgS, a relevant astrophysical problem for carbon rich stars, we have employed quantum mechanical ab initio calculations to predict the radiative association cross section and association rate coefficient of magnesium and sulfur atoms forming the magnesium sulfide molecule. This was accomplished by accounting for the emissive 11Π → X1Σ+, 11Δ → 11Π, and 13Σ− →a3Π transitions that make significant contributions to the radiative association process. The atomic ground state, Mg(1S), and the metastable excited state, S(1D), represent the lowest singlet dissociation limit common for the studied radiative association channels, whereas the ground states Mg(1S) and S(3P) represent the lowest triplet dissociation limit for these channels. The computational results show that in the temperature range of 10-10 000 K, the 11Π → X1Σ+ transition dominates the formation of MgS through radiative association in the collision of Mg(1S) and S(1D) atoms, while the 11Δ → 11Π transition plays an important role at higher temperatures. The total rate coefficient for the singlet-singlet transitions ranges from 3.78 × 10−18 cm3 s−1 to 4.79 × 10−17 cm3 s−1, while that for the triplet-triplet transition ranges from 2.02 × 10−22 cm3 s−1 to 6.79 × 10−18 cm3 s−1. These total rate coefficients were fit using the three-parameter fit Arrhenius-Kooij function, which is expected to be helpful for the celestial modeling.
期刊介绍:
Astronomy & Astrophysics is an international Journal that publishes papers on all aspects of astronomy and astrophysics (theoretical, observational, and instrumental) independently of the techniques used to obtain the results.