Josie R. Glenn, J.E. Isert, Jacob D. Bethke, Gamil A. Guirgis, G.S. Grubbs II
{"title":"The microwave spectrum of the low energy conformers of 1-ethylsilacyclopentane","authors":"Josie R. Glenn, J.E. Isert, Jacob D. Bethke, Gamil A. Guirgis, G.S. Grubbs II","doi":"10.1016/j.jms.2023.111872","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111872","url":null,"abstract":"<p>The microwave rotational spectrum of 1-ethylsilacyclopentane has been observed using chirped-pulse, Fourier transform microwave spectroscopy and has been reported for the first time. The lowest three energetic conformers were observed and fit to a Watson S semirigid Hamiltonian to within experimental accuracy. The quantum chemical calculations are all within ≈1% of the determined rotational constants, providing confidence that they are accurate representations of the experimental structure. Centrifugal distortion terms <em>D<sub>JK</sub></em> and <em>D<sub>K</sub></em>, although seemingly large, have been determined to be physically meaningful as no apparent evidence such as splittings in the spectrum or transition broadening was observed. A second moment analysis was undertaken and compared to similar silacyclopentanes, but it is not clear if this species follows previously determined trends.</p>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139022394","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":"Analysis of the calculated and observed X-X ro-vibrational transition intensities in molecular hydrogen","authors":"V.G. Ushakov , S.A. Balashev , E.S. Medvedev","doi":"10.1016/j.jms.2023.111863","DOIUrl":"10.1016/j.jms.2023.111863","url":null,"abstract":"<div><p>The potential-energy and quadrupole-moment functions of the H<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> ground electronic state are well known in literature (Komasa et al., 2019; Wolniewicz et al., 1998), and the line list of the vibrational–rotational transitions was calculated (Roueff et al., 2019). In this paper, we analyze the calculated intensities in order to learn how the intensities will change when analytic quadrupole-moment functions fitted to the <em>ab initio</em> and experimental data are used instead of spline-interpolated functions. We found that the use of splines does not deteriorate the intensities and does not lead to nonphysical saturation, as in heavier molecules, owing to the high precision of the <em>ab initio</em> data and the high density of the grid. The accuracy of the calculated intensities is estimated up to high overtones. Extraction of new spectroscopic information from the observational data that supplements the laboratory measurements is performed. The laboratory and observational data do not help increase the quality of the analytic functions. Numerous anomalies resulting from the destructive interference are identified in the calculated line lists, some of them being situated within the recently observed spectral regions, 1.5–<span><math><mrow><mn>2</mn><mo>.</mo><mn>5</mn><mspace></mspace><mi>μ</mi><mi>m</mi></mrow></math></span>. The intensities of these anomalies can be sensitive to the form of the molecular functions as well as to the proton-to-electron mass ratio. In this connection, the similar Le Roy anomalies (Brown and LeRoy, 1973; Le Roy and Vrscay, 1975) also arising due to the destructive interference in the Lyman and Werner systems are discussed.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138529739","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}
Adam M. Daly, Rhett P. Hill, Myla G. Gonzalez, Stephen G. Kukolich
{"title":"Microwave measurements and structure calculations for a glyoxylic acid – Water complex","authors":"Adam M. Daly, Rhett P. Hill, Myla G. Gonzalez, Stephen G. Kukolich","doi":"10.1016/j.jms.2023.111862","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111862","url":null,"abstract":"<div><p>The microwave spectra for a hydrogen-bonded <em>trans</em>-2 glyoxylic acid–water complex were measured in the 6–16 GHz frequency range using two Flygare-Balle type pulsed beam Fourier transform microwave (FTMW) spectrometers. The rotational constants for the dimer were determined to have the following values: A = 9384.2354(31), B = 1707.63973(73), and C = 1447.44879(56) MHz. The hydrogen bonded structures and rotational constants were calculated for the lowest energy dimglyoxylic acid - water using DFT, MP2 and CCSD calculations with various basis sets. The B3LYP/aug-cc-PVQZ-DG3 calculations yielded rotational constants of A = 9393.59, B = 1713.76, and C = 1453.23 MHz, in very good agreement with experimental values. The calculations show two feasible tunneling motions involving hydrogen atoms in this complex.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138489844","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}
George A. Pitsevich , Alex E. Malevich , Uladzimir U. Sapeshka
{"title":"Potential and kinetic interaction of two internal tops in molecules belonging to C2v(M) molecular symmetry group","authors":"George A. Pitsevich , Alex E. Malevich , Uladzimir U. Sapeshka","doi":"10.1016/j.jms.2023.111860","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111860","url":null,"abstract":"<div><p>Fourier analysis of the kinetic and potential interactions of non-coaxial internal tops in the molecules C<sub>6</sub>H<sub>4</sub>(OH)<sub>2</sub>, HO(CH<sub>2</sub>)OH, HOOOH, HOSOH, HSSSH, and HSOSH was carried out. It was found that for the all six molecules, in which both tops are characterized by a period 2 <span><math><mi>π</mi></math></span>, the harmonics with a period of <span><math><mi>π</mi></math></span> are dominate, with its contribution to the Fourier representation of potential surfaces increasing in the sequence mentioned above. Contributions of internal tops interactions to the kinetic and potential energies were determined for analyzed molecules. The influence of potential and kinetic interactions of internal tops on 1) the features of tunneling splitting of the ground and excited torsional states of molecules, 2) the landscape of 2D potential energy surfaces, 3) frequencies of fundamental torsional vibrations of hydroxyl and thiol groups, 4) the ratio of trans - and <em>cis</em> - conformer energies is also analyzed.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138447972","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}
Nathan A. Seifert , Branko Ruscic , Raghu Sivaramakrishnan , Kirill Prozument
{"title":"The C2H4O isomers in the oxidation of ethylene","authors":"Nathan A. Seifert , Branko Ruscic , Raghu Sivaramakrishnan , 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 SiO<sub>2</sub>/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 (CH<sub>2</sub>O), methoxy (CH<sub>3</sub>O), methanol (CH<sub>3</sub>OH), ketene (CH<sub>2</sub>CO), acetaldehyde (CH<sub>3</sub>CHO), <em>syn</em>-vinyl alcohol (<em>syn</em>-CH<sub>2</sub>CHOH), <em>anti</em>-vinyl alcohol (<em>anti</em>-CH<sub>2</sub>CHOH), oxirane (<em>c</em>-CH<sub>2</sub>OCH<sub>2</sub>), propyne (CH<sub>3</sub>CCH), and <em>syn</em>-propanal (<em>syn</em>-CH<sub>3</sub>CH<sub>2</sub>CHO). We focus on the three C<sub>2</sub>H<sub>4</sub>O species and deduce their concentration ratio [CH<sub>3</sub>CHO]:[CH<sub>2</sub>CHOH]:[<em>c</em>-CH<sub>2</sub>OCH<sub>2</sub>] = 1:0.7(2):0.06(2) by comparing the observed line intensities to those simulated with the PGOPHER software. Detailed thermochemistry of the C<sub>2</sub>H<sub>4</sub>O 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 C<sub>2</sub>H<sub>4</sub>O isomers is analyzed using a 0-D homogenous reactor kinetics simulation for ethylene oxidation. The ratios of the C<sub>2</sub>H<sub>4</sub>O isomers concentrations predicted by the kinetic model are compared to the experimental values.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":null,"pages":null},"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, 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<sup>−1</sup>. 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":null,"pages":null},"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}
P. Matisha Dorman, Brian J. Esselman, Maria A. Zdanovskaia, R. Claude Woods, Robert J. McMahon
{"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, Brian J. Esselman, Maria A. Zdanovskaia, R. Claude Woods, 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><sub>fit</sub></em> < 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, ν<sub>30</sub> (A″, 154 cm<sup>−1</sup>) and ν<sub>21</sub> (A′, 175 cm<sup>−1</sup>), 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<sup>−1</sup> 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":null,"pages":null},"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, 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":null,"pages":null},"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}
Marcel Bast , Julian Böing , Thomas Salomon , Sven Thorwirth , Oskar Asvany , Mathias Schäfer , Stephan Schlemmer
{"title":"Ro-vibrational spectra of CC stretching modes of C3H+ and HC3O+","authors":"Marcel Bast , Julian Böing , Thomas Salomon , Sven Thorwirth , Oskar Asvany , Mathias Schäfer , 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 C<sub>3</sub>H<sup>+</sup> and HC<sub>3</sub>O<sup>+</sup> 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> (C<sub>3</sub>H<sup>+</sup>) and <span><math><msub><mrow><mi>ν</mi></mrow><mrow><mn>3</mn></mrow></msub></math></span> (HC<sub>3</sub>O<sup>+</sup>) 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":null,"pages":null},"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}
Valentin Hermann , Anne Freise , Magnus Schlösser , Frank Hase , Johannes Orphal
{"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 , Anne Freise , Magnus Schlösser , Frank Hase , 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":null,"pages":null},"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}