{"title":"H2、HD和D2中F1Σg+外井态的光谱研究","authors":"K.-F. Lai, M. Beyer, W. Ubachs","doi":"10.1016/j.jms.2023.111778","DOIUrl":null,"url":null,"abstract":"<div><p>Two-photon UV-photolysis of hydrogen sulfide molecules is applied to produce hydrogen molecules in highly excited vibrational levels in the X<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> electronic ground state, up to the dissociation energy and into the quasibound region. Photolysis precursors H<sub>2</sub>S, HDS and D<sub>2</sub>S are used to produce vibrationally hot H<sub>2</sub>, HD and D<sub>2</sub>. The wave function density at large internuclear separation is excited via two-photon transitions in the F<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> - X<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> system to probe ro-vibrational levels in the first F<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> outer well state of <em>gerade</em> symmetry. Combining with accurate knowledge of the X<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> (<span><math><mrow><mi>v</mi><mo>,</mo><mi>J</mi></mrow></math></span>) levels from advanced ab initio calculations, energies of rovibrational levels in the F<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> state are determined. For the H<sub>2</sub> isotopologue a three-laser scheme is employed yielding level energies at accuracies of <span><math><mrow><mn>4</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup></mrow></math></span> cm<sup>−1</sup> for F(<span><math><mrow><mi>v</mi><mo>=</mo><mn>0</mn><mo>,</mo><mi>J</mi></mrow></math></span>) up to <span><math><mrow><mi>J</mi><mo>=</mo><mn>21</mn></mrow></math></span> and for some low <span><math><mi>J</mi></math></span> values of F(<span><math><mrow><mi>v</mi><mo>=</mo><mn>1</mn></mrow></math></span>). A two-laser scheme was applied to determine level energies in H<sub>2</sub> for F(<span><math><mrow><mi>v</mi><mo>=</mo><mn>0</mn><mo>−</mo><mn>4</mn></mrow></math></span>) levels as well as for various F levels in HD and D<sub>2</sub>, also up to large rotational quantum numbers. The latter measurements in the two-laser scheme are performed at lower resolution and the accuracy is strongly limited to 0.5 cm<sup>−1</sup> by ac-Stark effects. For H<sub>2</sub> a new quasibound resonance X<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> (<span><math><mrow><mi>v</mi><mo>=</mo><mn>6</mn></mrow></math></span>, <span><math><mrow><mi>J</mi><mo>=</mo><mn>23</mn></mrow></math></span>) is detected through the Q(23) and O(23) transitions in the F0-X6 band. Also a quasi-bound resonance in D<sub>2</sub> is assigned, for the first time in this species: X<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> (<span><math><mrow><mi>v</mi><mo>=</mo><mn>17</mn></mrow></math></span> , <span><math><mrow><mi>J</mi><mo>=</mo><mn>15</mn></mrow></math></span>). The experimental results on F(<span><math><mrow><mi>v</mi><mo>,</mo><mi>J</mi></mrow></math></span>) level energies are compared with previously reported theoretical results from multi-channel quantum-defect calculations as well as with results from newly performed non-adiabatic quantum calculations.</p></div>","PeriodicalId":16367,"journal":{"name":"Journal of Molecular Spectroscopy","volume":null,"pages":null},"PeriodicalIF":1.4000,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Spectroscopic study of the F1Σg+ outer well state in H2, HD and D2\",\"authors\":\"K.-F. Lai, M. Beyer, W. Ubachs\",\"doi\":\"10.1016/j.jms.2023.111778\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><p>Two-photon UV-photolysis of hydrogen sulfide molecules is applied to produce hydrogen molecules in highly excited vibrational levels in the X<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> electronic ground state, up to the dissociation energy and into the quasibound region. Photolysis precursors H<sub>2</sub>S, HDS and D<sub>2</sub>S are used to produce vibrationally hot H<sub>2</sub>, HD and D<sub>2</sub>. The wave function density at large internuclear separation is excited via two-photon transitions in the F<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> - X<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> system to probe ro-vibrational levels in the first F<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> outer well state of <em>gerade</em> symmetry. Combining with accurate knowledge of the X<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> (<span><math><mrow><mi>v</mi><mo>,</mo><mi>J</mi></mrow></math></span>) levels from advanced ab initio calculations, energies of rovibrational levels in the F<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> state are determined. For the H<sub>2</sub> isotopologue a three-laser scheme is employed yielding level energies at accuracies of <span><math><mrow><mn>4</mn><mo>×</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup></mrow></math></span> cm<sup>−1</sup> for F(<span><math><mrow><mi>v</mi><mo>=</mo><mn>0</mn><mo>,</mo><mi>J</mi></mrow></math></span>) up to <span><math><mrow><mi>J</mi><mo>=</mo><mn>21</mn></mrow></math></span> and for some low <span><math><mi>J</mi></math></span> values of F(<span><math><mrow><mi>v</mi><mo>=</mo><mn>1</mn></mrow></math></span>). A two-laser scheme was applied to determine level energies in H<sub>2</sub> for F(<span><math><mrow><mi>v</mi><mo>=</mo><mn>0</mn><mo>−</mo><mn>4</mn></mrow></math></span>) levels as well as for various F levels in HD and D<sub>2</sub>, also up to large rotational quantum numbers. The latter measurements in the two-laser scheme are performed at lower resolution and the accuracy is strongly limited to 0.5 cm<sup>−1</sup> by ac-Stark effects. For H<sub>2</sub> a new quasibound resonance X<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> (<span><math><mrow><mi>v</mi><mo>=</mo><mn>6</mn></mrow></math></span>, <span><math><mrow><mi>J</mi><mo>=</mo><mn>23</mn></mrow></math></span>) is detected through the Q(23) and O(23) transitions in the F0-X6 band. Also a quasi-bound resonance in D<sub>2</sub> is assigned, for the first time in this species: X<span><math><mrow><msup><mrow></mrow><mrow><mn>1</mn></mrow></msup><msubsup><mrow><mi>Σ</mi></mrow><mrow><mi>g</mi></mrow><mrow><mo>+</mo></mrow></msubsup></mrow></math></span> (<span><math><mrow><mi>v</mi><mo>=</mo><mn>17</mn></mrow></math></span> , <span><math><mrow><mi>J</mi><mo>=</mo><mn>15</mn></mrow></math></span>). The experimental results on F(<span><math><mrow><mi>v</mi><mo>,</mo><mi>J</mi></mrow></math></span>) level energies are compared with previously reported theoretical results from multi-channel quantum-defect calculations as well as with results from newly performed non-adiabatic quantum calculations.</p></div>\",\"PeriodicalId\":16367,\"journal\":{\"name\":\"Journal of Molecular Spectroscopy\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.4000,\"publicationDate\":\"2023-03-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Molecular Spectroscopy\",\"FirstCategoryId\":\"101\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S0022285223000437\",\"RegionNum\":4,\"RegionCategory\":\"物理与天体物理\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"PHYSICS, ATOMIC, MOLECULAR & CHEMICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Molecular Spectroscopy","FirstCategoryId":"101","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0022285223000437","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"PHYSICS, ATOMIC, MOLECULAR & CHEMICAL","Score":null,"Total":0}
Spectroscopic study of the F1Σg+ outer well state in H2, HD and D2
Two-photon UV-photolysis of hydrogen sulfide molecules is applied to produce hydrogen molecules in highly excited vibrational levels in the X electronic ground state, up to the dissociation energy and into the quasibound region. Photolysis precursors H2S, HDS and D2S are used to produce vibrationally hot H2, HD and D2. The wave function density at large internuclear separation is excited via two-photon transitions in the F - X system to probe ro-vibrational levels in the first F outer well state of gerade symmetry. Combining with accurate knowledge of the X () levels from advanced ab initio calculations, energies of rovibrational levels in the F state are determined. For the H2 isotopologue a three-laser scheme is employed yielding level energies at accuracies of cm−1 for F() up to and for some low values of F(). A two-laser scheme was applied to determine level energies in H2 for F() levels as well as for various F levels in HD and D2, also up to large rotational quantum numbers. The latter measurements in the two-laser scheme are performed at lower resolution and the accuracy is strongly limited to 0.5 cm−1 by ac-Stark effects. For H2 a new quasibound resonance X (, ) is detected through the Q(23) and O(23) transitions in the F0-X6 band. Also a quasi-bound resonance in D2 is assigned, for the first time in this species: X ( , ). The experimental results on F() level energies are compared with previously reported theoretical results from multi-channel quantum-defect calculations as well as with results from newly performed non-adiabatic quantum calculations.
期刊介绍:
The Journal of Molecular Spectroscopy presents experimental and theoretical articles on all subjects relevant to molecular spectroscopy and its modern applications. An international medium for the publication of some of the most significant research in the field, the Journal of Molecular Spectroscopy is an invaluable resource for astrophysicists, chemists, physicists, engineers, and others involved in molecular spectroscopy research and practice.