Journal of Molecular Spectroscopy最新文献

{"title":"The C2H4O isomers in the oxidation of ethylene","authors":"Nathan A. Seifert ,&nbsp;Branko Ruscic ,&nbsp;Raghu Sivaramakrishnan ,&nbsp;Kirill Prozument","doi":"10.1016/j.jms.2023.111847","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111847","url":null,"abstract":"<div><p>A combined rotational spectroscopy, thermochemistry, and kinetic modeling study explores the mechanism of acetaldehyde (ethanal), vinyl alcohol (ethenol), and ethylene oxide (oxirane) formation in the oxidation of ethylene (ethene). Multiplexed quantitative detection of oxidation intermediates and products exiting a SiO₂/SiC microreactor at 1700 K is demonstrated with the BrightSpec W-band chirped-pulse Fourier transform millimeter-wave spectrometer. The broadband rotational spectrum contains transitions of formaldehyde (CH₂O), methoxy (CH₃O), methanol (CH₃OH), ketene (CH₂CO), acetaldehyde (CH₃CHO), <em>syn</em>-vinyl alcohol (<em>syn</em>-CH₂CHOH), <em>anti</em>-vinyl alcohol (<em>anti</em>-CH₂CHOH), oxirane (<em>c</em>-CH₂OCH₂), propyne (CH₃CCH), and <em>syn</em>-propanal (<em>syn</em>-CH₃CH₂CHO). We focus on the three C₂H₄O species and deduce their concentration ratio [CH₃CHO]:[CH₂CHOH]:[<em>c</em>-CH₂OCH₂] = 1:0.7(2):0.06(2) by comparing the observed line intensities to those simulated with the PGOPHER software. Detailed thermochemistry of the C₂H₄O isomers and conformers is provided by Active Thermochemical Tables. The observed excess concentrations of vinyl alcohol and oxirane relative to the more stable acetaldehyde compared to the equilibrium ratio at 1700 K (1:0.087:0.000024), point to direct chemical pathways to these higher energy isomers. The mechanism for the formation of the three C₂H₄O isomers is analyzed using a 0-D homogenous reactor kinetics simulation for ethylene oxidation. The ratios of the C₂H₄O isomers concentrations predicted by the kinetic model are compared to the experimental values.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"398 ","pages":"Article 111847"},"PeriodicalIF":1.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92100879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Manifestation of binary collisions in the Raman-allowed bending vibrational band of the SF6 molecule","authors":"Florent Rachet,&nbsp;Michael Chrysos","doi":"10.1016/j.jms.2023.111857","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111857","url":null,"abstract":"<div><p>A careful, principally experimental Raman study which puts the focus on the <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>5</mn></mrow></msub></math></span> bending vibrational band by gaseous room-temperature sulfur hexafluoride is reported. In essence, our results boil down in the following two findings. Firstly, the anisotropic Raman-allowed spectrum by that band, which for the first time was isolated from the recordings and calibrated on an absolute scale. Secondly, an absolute-calibrated binary collision-induced component, which was also for the first time extracted from the crude measurements in the wavenumber range 475–570 cm⁻¹. Both spectra are depolarized and lead to parameters in agreement with the existing literature. The reported findings bring us one step closer to understanding how vibration mechanisms work in S<span><math><msub><mrow><mi>F</mi></mrow><mrow><mn>6</mn></mrow></msub></math></span> and show among other things that, at the <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>5</mn></mrow></msub></math></span> frequency, collisions between molecules enhance light scattering by 0.8% at 1 atm and by 13% at 15 atm of sulfur hexafluoride gas pressure.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"398 ","pages":"Article 111857"},"PeriodicalIF":1.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92046565","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The 130 – 750 GHz rotational spectrum of 2-cyanopyridine – Analysis of the ground vibrational state and the Coriolis-coupled dyad of its lowest-energy fundamental states","authors":"P. Matisha Dorman,&nbsp;Brian J. Esselman,&nbsp;Maria A. Zdanovskaia,&nbsp;R. Claude Woods,&nbsp;Robert J. McMahon","doi":"10.1016/j.jms.2023.111842","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111842","url":null,"abstract":"<div><p>The millimeter-wave rotational spectrum of 2-cyanopyridine was collected from 130 to 750 GHz, and the ground and two lowest-energy excited vibrational states were analyzed. In total, over 20,000 rotational transitions were least-squares fit for the three vibrational states to partial-octic, distorted-rotor Hamiltonians with low error (σ<em>_fit</em> &lt; 50 kHz). For the ground state, the many thousands of newly measured rotational transitions enabled substantial refinement of the rotational constants and determination of the centrifugal distortion constants. The rotational spectrum was collected at room temperature, permitting the observation of the two lowest-energy fundamental modes, ν₃₀ (A″, 154 cm⁻¹) and ν₂₁ (A′, 175 cm⁻¹), and determination of their spectroscopic constants. The two excited vibrational states are Coriolis coupled and require a two-state Hamiltonian. Eight Coriolis-coupling parameters (<span><math><mrow><msub><mi>G</mi><mi>a</mi></msub><mo>,</mo><msubsup><mi>G</mi><mrow><mi>a</mi></mrow><mi>J</mi></msubsup><mo>,</mo><msubsup><mi>G</mi><mrow><mi>a</mi></mrow><mi>K</mi></msubsup><mo>,</mo><msubsup><mi>G</mi><mrow><mi>a</mi></mrow><mrow><mi>JJ</mi></mrow></msubsup><mo>,</mo><msub><mi>F</mi><mrow><mi>bc</mi></mrow></msub><mo>,</mo><msubsup><mi>F</mi><mrow><mi>bc</mi></mrow><mi>J</mi></msubsup><mo>,</mo><msub><mi>G</mi><mi>b</mi></msub><mo>,</mo></mrow></math></span>and <span><math><mrow><msubsup><mi>G</mi><mrow><mi>b</mi></mrow><mi>J</mi></msubsup></mrow></math></span>) have been determined, as well as a precise energy difference of 26.524 312 6 (40) cm⁻¹ between the vibrational states. A comparison of the ground-state spectroscopic constants, as well as the Coriolis coupling-related parameters of analogous dyads is presented for multiple cyanoarenes.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"398 ","pages":"Article 111842"},"PeriodicalIF":1.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91963766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Taming semi-empirical methods for PAHs and vibrational spectra","authors":"Brent R. Westbrook,&nbsp;Ryan C. Fortenberry","doi":"10.1016/j.jms.2023.111846","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111846","url":null,"abstract":"<div><p>Semi-empirical methods offer a cost-effective means of computing explicit, anharmonic vibrational frequencies for large molecules, such as polycyclic aromatic hydrocarbons (PAHs), but their default parameters produce insufficiently accurate results for comparison to experiment, especially in the hydride stretching region where the NIRSpec instrument on JWST is most effective. This work delivers several reparameterized variants of the PM6 semi-empirical method trained to reproduce the experimental vibrational frequencies of 5 small hydrocarbon molecules. When benchmarked on the experimental frequencies of benzene and naphthalene, these reparameterized methods match the empirical values to within 38.7 cm<span><math><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span> on average. Combining these values with the default PM6 frequencies below 3000 cm<span><math><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span> brings the average deviation below 22 cm<span><math><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span> for naphthalene, comparing favorably with the existing state of the art in B3LYP/4-31G, for a two order of magnitude decrease in the computational cost. As such, the present work offers a promising means of extending the computation of explicit, anharmonic vibrational frequencies to PAHs larger than those that can be examined anharmonically via B3LYP. Such large and accurate data sets are necessary to disentangle the unidentified spectral features observed around myriad astronomical bodies and the influx of observational data from JWST.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"398 ","pages":"Article 111846"},"PeriodicalIF":1.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91963767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ro-vibrational spectra of CC stretching modes of C3H＋ and HC3O＋","authors":"Marcel Bast ,&nbsp;Julian Böing ,&nbsp;Thomas Salomon ,&nbsp;Sven Thorwirth ,&nbsp;Oskar Asvany ,&nbsp;Mathias Schäfer ,&nbsp;Stephan Schlemmer","doi":"10.1016/j.jms.2023.111840","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111840","url":null,"abstract":"<div><p>The carbon-rich molecular ions C₃H^＋ and HC₃O^＋ have been studied for the first time at high spectral resolution in the <span><math><mrow><mn>5</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span> wavelength regime employing leak-out spectroscopy of their <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>2</mn></mrow></msub></math></span> (C₃H^＋) and <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>3</mn></mrow></msub></math></span> (HC₃O^＋) vibrational fundamentals. All measurements were performed in a newly built cryogenic 22-pole ion trap apparatus, the COLtrap II instrument. Besides the action spectroscopic characterization the new measurements have also been used towards optimization and an improved understanding of the leak-out process via a semi-quantitative kinetics model for which some rates are determined or estimated and rationalized.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"398 ","pages":"Article 111840"},"PeriodicalIF":1.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0022285223001054/pdfft?md5=5c1d032b5c3187a00d5bedd92ca59b6c&pid=1-s2.0-S0022285223001054-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92100878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Observation and assignment of a high-resolution FTIR-spectrum of T216O, DT16O and HT16O in the range of 4300 to 4700cm−1","authors":"Valentin Hermann ,&nbsp;Anne Freise ,&nbsp;Magnus Schlösser ,&nbsp;Frank Hase ,&nbsp;Johannes Orphal","doi":"10.1016/j.jms.2023.111859","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111859","url":null,"abstract":"<div><p>In the range of <span><math><mrow><mn>4300</mn></mrow></math></span> to <span><math><mrow><mtext>4700</mtext><mspace></mspace><mtext>cm</mtext><msup><mrow></mrow><mrow><mi>−1</mi></mrow></msup></mrow></math></span>, we present analysis of the <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>1</mn></mrow></msub></mrow></math></span>, <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span>+<span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>3</mn></mrow></msub></math></span> and <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span>+<span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>3</mn></mrow></msub></math></span> bands of T<span><math><msubsup><mrow></mrow><mrow><mn>2</mn></mrow><mrow><mn>16</mn></mrow></msubsup></math></span>O, the <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>1</mn></mrow></msub></mrow></math></span> and <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span>+<span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>2</mn></mrow></msub></mrow></math></span> of DT<span><math><msup><mrow></mrow><mrow><mn>16</mn></mrow></msup></math></span>O and the <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>1</mn></mrow></msub></mrow></math></span> of HT<span><math><msup><mrow></mrow><mrow><mn>16</mn></mrow></msup></math></span>O. The analysed high-resolution spectrum has been obtained from a Bruker IFS 125HR Fourier-transform spectrometer with a resolution of <span><math><mrow><mtext>0.025</mtext><mspace></mspace><mtext>cm</mtext><msup><mrow></mrow><mrow><mi>−1</mi></mrow></msup></mrow></math></span> using an optical cell with an activity of <span><math><mrow><mtext>10</mtext><mspace></mspace><mtext>GBq</mtext></mrow></math></span>. For the in total 2436 lines an individual positional uncertainty of up to <span><math><mrow><mtext>3.4</mtext><mo>×</mo><mtext>10</mtext><msup><mrow></mrow><mrow><mi>-5</mi></mrow></msup><mspace></mspace><mtext>cm</mtext><msup><mrow></mrow><mrow><mi>−1</mi></mrow></msup></mrow></math></span> and a systematic uncertainty of <span><math><mrow><mtext>7.5</mtext><mo>×</mo><mtext>10</mtext><msup><mrow></mrow><mrow><mi>-4</mi></mrow></msup><mspace></mspace><mtext>cm</mtext><msup><mrow></mrow><mrow><mi>−1</mi></mrow></msup></mrow></math></span> could be achieved. Four of the six bands have been analysed for the first time, the <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span>+<span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>3</mn></mrow></msub></math></span> band of T<span><math><msubsup><mrow></mrow><mrow><mn>2</mn></mrow><mrow><mn>16</mn></mrow></msubsup></math></span>O and the <span><math><mrow><mn>2</mn><msub><mrow><mi>ν</mi></mrow><mrow><mn>1</mn></mrow></msub></mrow></math></span> of HT<span><math><msup><mrow></mrow><mrow><mn>16</mn></mrow></msup></math></span><span>O have been analysed in","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"398 ","pages":"Article 111859"},"PeriodicalIF":1.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134832861","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Colin Western (1957–2021)","authors":"M.N.R. Ashfold,&nbsp;A.J. Orr-Ewing","doi":"10.1016/j.jms.2023.111858","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111858","url":null,"abstract":"","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"398 ","pages":"Article 111858"},"PeriodicalIF":1.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134832860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The database of spectroscopic constants of diatomic molecules (DSCDM): A dynamic and user-friendly interface for molecular physics and spectroscopy","authors":"Yueqian Wang ,&nbsp;Daniel Julian ,&nbsp;Mahmoud A.E. Ibrahim ,&nbsp;Connor Chin ,&nbsp;Saketh Bhattiprolu ,&nbsp;Ethan Franco ,&nbsp;Jesús Pérez-Ríos","doi":"10.1016/j.jms.2023.111848","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111848","url":null,"abstract":"<div><p>We present the database of spectroscopic constants of diatomic molecules (DSCDM), a website dedicated to the spectroscopic constants of ground and excited states of diatomics (<span>https://dscdm.physics.stonybrook.edu</span><svg><path></path></svg>). The database can be improved based on community feedback: the community as contributors may upload new data. Additionally, it counts on an Application Programming Interface (API) for molecular spectroscopy data retrieval to make the search process more efficient. On the other hand, the website presents a machine learning predictor of spectroscopic constants based on atomic properties and a new plotting tool to study the statistical distribution of spectroscopic constants.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"398 ","pages":"Article 111848"},"PeriodicalIF":1.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"92136232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The ground electronic state of CS: A global multi-isotopologue direct potential fit analysis","authors":"John A. Coxon ,&nbsp;Photos G. Hajigeorgiou","doi":"10.1016/j.jms.2023.111861","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111861","url":null,"abstract":"<div><p>A collection of 6759 pure-rotational and vibrational–rotational spectroscopic line positions available for seven isotopologues of the ground <span><math><mrow><mi>X</mi><msup><mrow><mspace></mspace></mrow><mn>1</mn></msup><msup><mi>Σ</mi><mo>+</mo></msup></mrow></math></span> electronic state of carbon monosulfide has been employed in a weighted nonlinear least-squares direct fit to the potential energy function of ¹²C³²S and supplementary functions describing breakdown of the Born-Oppenheimer approximation. All radial functions are represented by compact analytical models having proper theoretical asymptotic behavior. The spectroscopic line positions are reproduced on average to within the associated experimental uncertainties by the quantum–mechanical eigenvalues of the derived Hamiltonians for individual isotopologues. The potential energy function is constrained to obey the theoretical radial behavior both at short-range and at long-range. Accurate quantum–mechanical vibrational term values and rotational and centrifugal distortion constants are provided for all stable isotopologues of CS included in the least-squares fits.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"398 ","pages":"Article 111861"},"PeriodicalIF":1.4,"publicationDate":"2023-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138447944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The ground electronic state of ClF: Updated molecular constants and potential curves for 35ClF and 37ClF","authors":"Photos G. Hajigeorgiou","doi":"10.1016/j.jms.2023.111845","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111845","url":null,"abstract":"<div><p>A comprehensive assessment of available literature spectroscopic data and molecular constants for the <em>X</em> ¹Σ⁺ ground electronic states of isotopologues ³⁵ClF and ³⁷ClF is undertaken. Three different approaches are employed in the analysis of the available information. The first approach involves merging molecular constants from various studies to yield an optimized set of Dunham coefficients {<em>Y</em>₀₁, <em>Y</em>₀₂, <em>Y</em>₀₃, <em>Y</em>₁₀, <em>Y</em>₁₁, <em>Y</em>₂₁, <em>Y</em>₀₂ and <em>Y</em>₁₂}. Utilizing these updated constants, vibrational energies (<em>G_υ</em>) and rotational constants (<em>B_υ</em>) for <em>υ</em> = 0–9 are calculated, and RKR potentials are determined for both isotopologues. The second approach involves calculating synthetic spectroscopic line positions using literature molecular constants, with normally distributed random errors added on, and subjecting these to a modern direct-potential-fit analysis. This analysis produces a precise analytical potential energy function for ³⁵ClF, and Born-Oppenheimer breakdown functions that characterize adiabatic and non-adiabatic corrections. The third approach involves fitting the synthetic spectroscopic data directly to Dunham coefficients. The results of the three approaches are compared and discussed.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"398 ","pages":"Article 111845"},"PeriodicalIF":1.4,"publicationDate":"2023-10-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49765673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}