Journal of Molecular Spectroscopy最新文献

{"title":"The first observation of the 12C16O2 absorption bands near 660 nm","authors":"Yu.G. Borkov,&nbsp;A.M. Solodov,&nbsp;A.A. Solodov,&nbsp;T.M. Petrova,&nbsp;V.I. Perevalov","doi":"10.1016/j.jms.2023.111843","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111843","url":null,"abstract":"<div><p>The absorption spectra of carbon dioxide were recorded in the region from 15,000 to 15,300 cm⁻¹, using a Bruker IFS 125 HR Fourier transform spectrometer and a 30 m multipass cell with the White type optical system. The recording was performed at a spectral resolution of 0.044 – 0.050 cm⁻¹, room temperature, a path length of 1057.95 m and pressures of 185 and 362 mbar. Utilization of a LED as a light source provided a sensitivity (noise equivalent absorption) at the level of <em>k</em>_ν = 1.23 × 10^-10 cm⁻¹ and allowed detection of a number of lines of two 3005<em>i</em> − 00001 (<em>i</em> = 2,3) bands and several lines of the 60031 – 00001 band of ¹²C¹⁶O₂ with the intensity values down to 10^-30 cm⁻¹/(molecule cm⁻²) at 296 K. These bands were observed for the first time. The uncertainty of the line position measurements was estimated to be about 0.005 cm⁻¹ for the unblended lines with a high signal-to-noise ratio. The uncertainties of the retrieved line intensities for the strongest unblended lines are at the level of 15 %. The spectroscopic constants for observed bands were fitted to the observed line positions. The vibrational transition dipole moments squared of these bands were fitted to the observed line intensities. The measured line positions were compared to those from the HITRAN2020 database and to those predicted with the global effective Hamiltonian. The measured line intensities were compared to the values from the HITRAN2020 database and from the Ames2021 line list.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"397 ","pages":"Article 111843"},"PeriodicalIF":1.4,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49748529","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":"Effective Hamiltonians for calculation of rotational energy levels and relative intensities in open-shell clusters containing O2 (3","authors":"W. M. Fawzy","doi":"10.1016/j.jms.2023.111822","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111822","url":null,"abstract":"","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41347460","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 pressure effect on the line profiles observed in the ν1","authors":"S. Okubo, K. Iwakuni, Hideki Kato, F. Hong, H. Sasada, H. Inaba, K.M.T. Yamada","doi":"10.1016/j.jms.2023.111823","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111823","url":null,"abstract":"","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45540199","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 pressure effect on the line profiles observed in the ν1+ν3 band of acetylene: Revisited","authors":"Sho Okubo ,&nbsp;Kana Iwakuni ,&nbsp;Hideki Kato ,&nbsp;Feng-Lei Hong ,&nbsp;Hiroyuki Sasada ,&nbsp;Hajime Inaba ,&nbsp;Koichi M.T. Yamada","doi":"10.1016/j.jms.2023.111823","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111823","url":null,"abstract":"<div><p>In our previous paper [K. Iwakuni et al., <em>Phys. Rev. Lett.</em> <strong>117</strong>, 1439026 (2018)] the ortho-para dependence of the pressure effects was reported for the <span><math><mrow><msub><mrow><mi>ν</mi></mrow><mrow><mn>1</mn></mrow></msub><mo>+</mo><msub><mrow><mi>ν</mi></mrow><mrow><mn>3</mn></mrow></msub></mrow></math></span> band of acetylene measured by dual-comb spectroscopy. Sears and coworkers [E.C. Gross et al., <em>J. Chem. Phys.</em> <strong>154</strong>, 054305 (2021)] reevaluated the profile parameters for some lines of this band by comb-referenced laser spectroscopy, and pointed out that the ortho-para phenomenon must be a consequence of the use of Voigt function as the profile function, with the Doppler widths fixed at their theoretical values. Thus, we have remeasured this band with two improved spectrometers, the comb-locked laser spectrometer of the National Metrology Institute of Japan and another dual-comb spectrometer of Yokohama National University, and analyzed the lines by using the speed-dependent Voigt function as the profile function with several options. By the present work, we confirm the fact pointed out by Sears and coworkers, and present some remaining problems in the experimental determination of the line profile parameters.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"396 ","pages":"Article 111823"},"PeriodicalIF":1.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49750509","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":"Fourier transform infrared (FTIR) spectroscopy of formaldoxime isotopologue 12CD2NOH in the 300–3700 cm−1 region and its ν12 and ν9 bands: Vibrational and rovibrational analyses","authors":"A. Jusuf,&nbsp;T.L. Tan,&nbsp;Q.Y. Wu","doi":"10.1016/j.jms.2023.111812","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111812","url":null,"abstract":"<div><p>The Fourier transform infrared (FTIR) spectrum of the formaldoxime isotopologue ¹²CD₂NOH was recorded in the 500–3700 cm⁻¹ region with a resolution of 0.50 cm⁻¹ to identify its fundamental, overtone and combination bands and to measure their relative infrared (IR) band intensities. Furthermore, the high-resolution (0.00096 cm⁻¹) FTIR spectrum of <span><math><mrow><msub><mi>ν</mi><mn>12</mn></msub></mrow></math></span> and <span><math><mrow><msub><mi>ν</mi><mn>9</mn></msub></mrow></math></span> bands of ¹²CD₂<span>NOH was recorded in Australian Synchrotron in the 300–510 cm</span>⁻¹ region for a rovibrational analysis. A total of 1060 IR transitions of the <em>C</em>-type <span><math><mrow><msub><mi>ν</mi><mn>12</mn></msub></mrow></math></span> band were fitted using the Watson's <em>A</em>-reduced Hamiltonian in the <em>I^r</em> representation with a root-mean-square (rms) deviation of 0.000524 cm⁻¹. From the rovibrational analysis, the <span><math><mrow><msub><mi>v</mi><mn>12</mn></msub></mrow></math></span><span> = 1 state rovibrational constants up to all 5 quartic centrifugal distortion terms were derived for the first time. The band center of the </span><span><math><mrow><msub><mi>ν</mi><mn>12</mn></msub></mrow></math></span> band of ¹²CD₂NOH was found to be 391.214740(46) cm⁻¹. The ground state rovibrational constants up to all 5 quartic terms were determined for the first time by the fitting of 423 ground state combination differences (GSCDs) derived from the IR transitions of the <span><math><mrow><msub><mi>ν</mi><mn>12</mn></msub></mrow></math></span> band of ¹²CD₂NOH of this work. The rms deviation of the GSCD fit was 0.000473 cm⁻¹ using the Watson’s <em>A-</em>reduced Hamiltonian in the <em>I^r</em> representation. Furthermore, a total of 724 IR transitions of the predominantly <em>B</em>-type <span><math><mrow><msub><mi>ν</mi><mn>9</mn></msub></mrow></math></span> band of ¹²CD₂NOH were fitted with a rms deviation of 0.000360 cm⁻¹ to derive the band center at 465.151277(39) cm⁻¹ and rovibrational constants of the <span><math><mrow><msub><mi>v</mi><mn>9</mn></msub></mrow></math></span><span> = 1 state up to 4 quartic terms for the first time. Additionally, all 3 rotational constants and 5 quartic centrifugal distortion terms of the ground state and 3 rotational constants of the </span><span><math><mrow><msub><mi>v</mi><mn>12</mn></msub></mrow></math></span> = 1 and <span><math><mrow><msub><mi>v</mi><mn>9</mn></msub></mrow></math></span> = 1 states of ¹²CD₂<span>NOH were computed from theoretical anharmonic calculations at 2 different levels of theory, B3LYP and MP2 with the cc-pVTZ basis set, for comparison with the experimental results. Close agreement was found for the calculated ","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"396 ","pages":"Article 111812"},"PeriodicalIF":1.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49699463","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":"Extrapolation properties of the Morse-Long Range potential at large internuclear distances","authors":"A. Sinanaj,&nbsp;A. Pashov","doi":"10.1016/j.jms.2023.111811","DOIUrl":"10.1016/j.jms.2023.111811","url":null,"abstract":"<div><p><span>The accuracy of the potential energy curves for diatomic molecules determined from experimental data is confirmed empirically with numerous examples in the literature. Usually PECs are determined from a limited set of experimental data and this in turns limits the range of internuclear distances where the shape of the potential is unambiguously fixed. While the uncertainty for interpolation could be assessed, the extrapolation is usually questionable and needs careful analyses. The Morse/Long-Range potential (Le Roy and Henderson, 2007) has been reported to have a built in long-range asymptotic behavior and therefore it is plausible to expect that one can expect good extrapolation properties and even possibility to determine important molecular parameters like </span><span><math><msub><mrow><mi>D</mi></mrow><mrow><mi>e</mi></mrow></msub></math></span> or/and <span><math><msub><mrow><mi>C</mi></mrow><mrow><mi>m</mi></mrow></msub></math></span> from limited set of experimental data. In this contribution we undertake a systematic study which confirms these expectations in the case of Ca<span><math><msub><mrow></mrow><mrow><mn>2</mn></mrow></msub></math></span> ground state.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"396 ","pages":"Article 111811"},"PeriodicalIF":1.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42765915","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":"Fourier transform infrared (FTIR) spectroscopy of formaldoxime isotopologue 12CD2NOH in the 300-3700 cm-1 region and its ν12","authors":"A. Jusuf, T. L. Tan, Q.Y. Wu","doi":"10.1016/j.jms.2023.111812","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111812","url":null,"abstract":"","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":" ","pages":""},"PeriodicalIF":1.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49480809","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":"High-resolution absorption spectroscopy of room-temperature and jet-cooled ammonia between 59,000 and 93,000 cm−1","authors":"Stephen T. Pratt ,&nbsp;Ugo Jacovella ,&nbsp;Séverine Boyé-Péronne ,&nbsp;Michael N.R. Ashfold ,&nbsp;Denis Joyeux ,&nbsp;Nelson De Oliveira ,&nbsp;David M.P. Holland","doi":"10.1016/j.jms.2023.111810","DOIUrl":"10.1016/j.jms.2023.111810","url":null,"abstract":"<div><p>We present new high-resolution photoabsorption spectra of ammonia spanning the region between 59,000 cm⁻¹ and 93,000 cm⁻¹ that were recorded by using the Fourier Transform Spectrometer at the Synchrotron SOLEIL. This region extends from just above the Franck-Condon envelope for the <span><math><mover><mi>A</mi><mo>̃</mo></mover></math></span> ¹<span><math><mrow><msub><mi>A</mi><mrow><mn>2</mn></mrow></msub><mo>″</mo></mrow></math></span> ← <span><math><mover><mi>X</mi><mo>̃</mo></mover></math></span> ¹<span><math><mrow><msub><mi>A</mi><mrow><mn>1</mn></mrow></msub><mo>′</mo></mrow></math></span> transition to well above the NH₃⁺ <span><math><msup><mrow><mover><mi>X</mi><mo>̃</mo></mover></mrow><mo>+</mo></msup></math></span> ²<span><math><mrow><msub><mi>A</mi><mrow><mn>2</mn></mrow></msub><mo>″</mo></mrow></math></span> ionization threshold. The spectra were recorded at a measured resolution of 0.23 cm⁻¹ in both a room-temperature cell (293 K) and in a slit-jet supersonic expansion (∼70 K). The absolute photoabsorption cross section with an uncertainty of ± 5% is also reported for the room-temperature spectrum. The present resolution is a factor of 10 – 100 times higher than in other recently reported broad band spectra of ammonia, and many of the observed bands show partially resolved rotational structure. We have attempted to assign this structure for a number of these bands. The oscillator strengths extracted from the data are in good agreement with previous measurements but, in the case of structured bands, the present higher resolution measurements return higher peak absorption cross sections, that increase further when the sample is cooled. The present higher resolution spectra suggest that a number of previous vibronic band assignments that were based on quantum defect considerations may require some revision. Finally, we discuss the substantial differences between the photoabsorption and photoionization data just above the first ionization threshold.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"396 ","pages":"Article 111810"},"PeriodicalIF":1.4,"publicationDate":"2023-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41550825","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":"Improved potential-energy and dipole-moment functions of the ground electronic state of phosphorus nitride","authors":"V.G. Ushakov ,&nbsp;M. Semenov ,&nbsp;S.N. Yurchenko ,&nbsp;A. Yu. Ermilov ,&nbsp;E.S. Medvedev","doi":"10.1016/j.jms.2023.111804","DOIUrl":"https://doi.org/10.1016/j.jms.2023.111804","url":null,"abstract":"<div><p><em>Ab initio</em><span> calculations of the PN potential and electric dipole moment in the </span><span><math><mrow><msup><mrow><mi>X</mi></mrow><mrow><mn>1</mn></mrow></msup><msup><mrow><mi>Σ</mi></mrow><mrow><mo>+</mo></mrow></msup></mrow></math></span> ground electronic state were performed at short bond lengths, <span><math><mrow><mi>r</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>2</mn></mrow></math></span><span>–0.8 Å, and semi-empirical analytical potential-energy and dipole-moment functions were constructed based on all available experimental and theoretical information. The analytical forms for the potential-energy functions include the Extended Morse Oscillator and the Extended Hulburt-Hirshfelder potential. The dipole-moment function of PN was presented by our irregular and rational functions previously used for CO. The potential-energy and dipole-moment model functions were fitted simultaneously to the experimental line positions and permanent dipoles at </span><span><math><mrow><mi>v</mi><mo>=</mo><mn>0</mn></mrow></math></span>-2, as well as to the <em>ab initio</em> data from our present and previous studies. With these new functions, the improved line list for the ground electronic state of ³¹P¹⁴<span>N was calculated. We show that the new analytic representations of the potential and dipole moment functions help significantly reduce the numerical noise in the intensities of high overtones as well as the associated saturation at high wavenumbers leading to the so-called “overtone plateaus” in spectra of diatomic molecules (see Medvedev et al., J. Mol. Spectrosc., </span><strong>330</strong>, 36 (2016)) and thus provide reliable transition intensities at very high transition frequencies. The 3-0 band is identified as vibrational anomaly, and rotational anomalies inside this and some other bands are found.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"395 ","pages":"Article 111804"},"PeriodicalIF":1.4,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49727211","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":"Ab initio potential energy surface and vibration-rotation energy levels of magnesium monohydroxide revisited","authors":"Jacek Koput","doi":"10.1016/j.jms.2023.111805","DOIUrl":"10.1016/j.jms.2023.111805","url":null,"abstract":"<div><p><span>The accurate potential energy surface of magnesium monohydroxide, MgOH, in its ground electronic state </span><span><math><mrow><mover><mrow><mi>X</mi></mrow><mrow><mo>˜</mo></mrow></mover><msup><mrow><mspace></mspace></mrow><mrow><mn>2</mn></mrow></msup><msup><mrow><mi>Σ</mi></mrow><mrow><mo>+</mo></mrow></msup></mrow></math></span><span> has been determined from ab initio calculations<span><span> using the coupled-cluster approach in conjunction with the correlation-consistent basis sets up to septuple-zeta quality. The core-electron correlation, higher-order electron correlation, scalar relativistic, and adiabatic effects were taken into account. The equilibrium configuration of the MgOH molecule was confirmed to be linear, although with the bending </span>potential energy function being very flat near the minimum. The vibration–rotation-spin energy levels of the MgOH, MgOD, </span></span>²⁵MgOH, and ²⁶MgOH isotopologues were predicted using a variational approach. The spectroscopic constants of these isotopologues were determined to high accuracy.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":"395 ","pages":"Article 111805"},"PeriodicalIF":1.4,"publicationDate":"2023-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43645549","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}