Ziqiang Zhao, Shilin Hou, Yang Zhao, Pingsai Chu, Ye Tian
{"title":"用于激光诱导等离子体研究的CaF的B2Σ+-X2Σ+波段系统的扩展线列表。","authors":"Ziqiang Zhao, Shilin Hou, Yang Zhao, Pingsai Chu, Ye Tian","doi":"10.1063/5.0278000","DOIUrl":null,"url":null,"abstract":"<p><p>Calcium monofluoride (CaF) is an important species for the sensitive detection of fluorine with laser-induced breakdown spectroscopy (LIBS). A line list for the B2Σ+-X2Σ+ transition system of CaF was calculated and extended from v ≤ 20 to v = 35 using empirical potential functions obtained through a direct-potential fit approach with observed transition frequencies. The line strengths were predicted using the scaled transition dipole moments calculated ab initio. The simulated intensities and transition positions with the present line list agree well with the spectra of high-resolution molecular spectroscopy from the literature and of LIBS from this work. Based on the simulated spectra of the CaF B-X system, the derived temperatures with the LIBS spectra vary across different wavelength regions. For example, with the same spectrum of delay time t = 13 μs, the obtained temperatures with λ ≈ 514-529 nm and λ ≈ 514-570 nm are 4000 and 5500 K, respectively. However, this discrepancy decreases with increasing delay time. For t = 23 μs, the obtained temperatures (3700 ± 200-4000 ± 100 K) are already in agreement within the estimated uncertainties. Self-absorption in the spectrum also influences the simulated temperature. Excluding the influences from self-absorption, the derived temperature (6000 ± 200 K) with the CaF molecular spectrum of λ ≈ 529-542 nm of t = 13 μs is close to the ionization temperature (6600 K) obtained with the Saha-Boltzmann fit from the observed atomic/ionic lines of Ca in the plasma. The present line list can be adopted in plasma diagnostics and in sensitive detections of fluorine with the CaF spectrum in hot environments.</p>","PeriodicalId":15313,"journal":{"name":"Journal of Chemical Physics","volume":"163 8","pages":""},"PeriodicalIF":3.1000,"publicationDate":"2025-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Extended line list for the B2Σ+-X2Σ+ band system of CaF for use in laser-induced plasma studies.\",\"authors\":\"Ziqiang Zhao, Shilin Hou, Yang Zhao, Pingsai Chu, Ye Tian\",\"doi\":\"10.1063/5.0278000\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p><p>Calcium monofluoride (CaF) is an important species for the sensitive detection of fluorine with laser-induced breakdown spectroscopy (LIBS). A line list for the B2Σ+-X2Σ+ transition system of CaF was calculated and extended from v ≤ 20 to v = 35 using empirical potential functions obtained through a direct-potential fit approach with observed transition frequencies. The line strengths were predicted using the scaled transition dipole moments calculated ab initio. The simulated intensities and transition positions with the present line list agree well with the spectra of high-resolution molecular spectroscopy from the literature and of LIBS from this work. Based on the simulated spectra of the CaF B-X system, the derived temperatures with the LIBS spectra vary across different wavelength regions. For example, with the same spectrum of delay time t = 13 μs, the obtained temperatures with λ ≈ 514-529 nm and λ ≈ 514-570 nm are 4000 and 5500 K, respectively. However, this discrepancy decreases with increasing delay time. For t = 23 μs, the obtained temperatures (3700 ± 200-4000 ± 100 K) are already in agreement within the estimated uncertainties. Self-absorption in the spectrum also influences the simulated temperature. Excluding the influences from self-absorption, the derived temperature (6000 ± 200 K) with the CaF molecular spectrum of λ ≈ 529-542 nm of t = 13 μs is close to the ionization temperature (6600 K) obtained with the Saha-Boltzmann fit from the observed atomic/ionic lines of Ca in the plasma. The present line list can be adopted in plasma diagnostics and in sensitive detections of fluorine with the CaF spectrum in hot environments.</p>\",\"PeriodicalId\":15313,\"journal\":{\"name\":\"Journal of Chemical Physics\",\"volume\":\"163 8\",\"pages\":\"\"},\"PeriodicalIF\":3.1000,\"publicationDate\":\"2025-08-28\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Chemical Physics\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://doi.org/10.1063/5.0278000\",\"RegionNum\":2,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"CHEMISTRY, PHYSICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Chemical Physics","FirstCategoryId":"92","ListUrlMain":"https://doi.org/10.1063/5.0278000","RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, PHYSICAL","Score":null,"Total":0}
Extended line list for the B2Σ+-X2Σ+ band system of CaF for use in laser-induced plasma studies.
Calcium monofluoride (CaF) is an important species for the sensitive detection of fluorine with laser-induced breakdown spectroscopy (LIBS). A line list for the B2Σ+-X2Σ+ transition system of CaF was calculated and extended from v ≤ 20 to v = 35 using empirical potential functions obtained through a direct-potential fit approach with observed transition frequencies. The line strengths were predicted using the scaled transition dipole moments calculated ab initio. The simulated intensities and transition positions with the present line list agree well with the spectra of high-resolution molecular spectroscopy from the literature and of LIBS from this work. Based on the simulated spectra of the CaF B-X system, the derived temperatures with the LIBS spectra vary across different wavelength regions. For example, with the same spectrum of delay time t = 13 μs, the obtained temperatures with λ ≈ 514-529 nm and λ ≈ 514-570 nm are 4000 and 5500 K, respectively. However, this discrepancy decreases with increasing delay time. For t = 23 μs, the obtained temperatures (3700 ± 200-4000 ± 100 K) are already in agreement within the estimated uncertainties. Self-absorption in the spectrum also influences the simulated temperature. Excluding the influences from self-absorption, the derived temperature (6000 ± 200 K) with the CaF molecular spectrum of λ ≈ 529-542 nm of t = 13 μs is close to the ionization temperature (6600 K) obtained with the Saha-Boltzmann fit from the observed atomic/ionic lines of Ca in the plasma. The present line list can be adopted in plasma diagnostics and in sensitive detections of fluorine with the CaF spectrum in hot environments.
期刊介绍:
The Journal of Chemical Physics publishes quantitative and rigorous science of long-lasting value in methods and applications of chemical physics. The Journal also publishes brief Communications of significant new findings, Perspectives on the latest advances in the field, and Special Topic issues. The Journal focuses on innovative research in experimental and theoretical areas of chemical physics, including spectroscopy, dynamics, kinetics, statistical mechanics, and quantum mechanics. In addition, topical areas such as polymers, soft matter, materials, surfaces/interfaces, and systems of biological relevance are of increasing importance.
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