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Horn KP, Vazquez-Salazar LI, Koch CP, Meuwly M. Improving potential energy surfaces using measured Feshbach resonance states. SCIENCE ADVANCES 2024; 10:eadi6462. [PMID: 38427733 PMCID: PMC10906917 DOI: 10.1126/sciadv.adi6462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 01/29/2024] [Indexed: 03/03/2024]
Abstract
The structure and dynamics of a molecular system is governed by its potential energy surface (PES), representing the total energy as a function of the nuclear coordinates. Obtaining accurate potential energy surfaces is limited by the exponential scaling of Hilbert space, restricting quantitative predictions of experimental observables from first principles to small molecules with just a few electrons. Here, we present an explicitly physics-informed approach for improving and assessing the quality of families of PESs by modifying them through linear coordinate transformations based on experimental data. We demonstrate this "morphing" of the PES for the He - H2+ complex using recent comprehensive Feshbach resonance (FR) measurements for reference PESs at three different levels of quantum chemistry. In all cases, the positions and intensities of peaks in the energy distributions are improved. We find these observables to be mainly sensitive to the long-range part of the PES.
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Affiliation(s)
- Karl P. Horn
- Dahlem Center for Complex Quantum Systems and Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany
| | | | - Christiane P. Koch
- Dahlem Center for Complex Quantum Systems and Fachbereich Physik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland
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2
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Liu QH, Tan Y, Cheng CF, Hu SM. Precision spectroscopy of molecular hydrogen. Phys Chem Chem Phys 2023; 25:27914-27925. [PMID: 37843424 DOI: 10.1039/d3cp03042c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2023]
Abstract
Precision measurements on the hydrogen molecule are of fundamental importance in understanding molecular theory. Comparison of accurate experimental data and theoretical results are used to test the quantum electrodynamics theory and determine physical constants used in the calculation. We review recent advances and perspectives in the precision spectroscopy of molecular hydrogen, representing state-of-the-art molecular spectroscopy methods and cutting-edge high-precision calculations.
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Affiliation(s)
- Qian-Hao Liu
- Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, China.
| | - Yan Tan
- Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, China.
| | - Cun-Feng Cheng
- Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, China.
| | - Shui-Ming Hu
- Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, China.
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3
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Irikura KK. Ab initio spectroscopy and thermochemistry of diatomic platinum hydride, PtH. J Chem Phys 2023; 158:2888845. [PMID: 37144716 DOI: 10.1063/5.0145567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 04/18/2023] [Indexed: 05/06/2023] Open
Abstract
Rovibrational levels of low-lying electronic states of the diatomic molecule PtH are computed using non-relativistic wavefunction methods and a relativistic core pseudopotential. Dynamical electron correlation is treated at the coupled-cluster with single and double excitations and a perturbative estimate of triple excitations level, with basis-set extrapolation. Spin-orbit coupling is treated by configuration interaction in a basis of multireference configuration interaction states. The results compare favorably with available experimental data, especially for low-lying electronic states. For the yet-unobserved first excited state, Ω = 1/2, we predict constants including Te = (2036 ± 300) cm-1 and ΔG1/2 = (2252.5 ± 8) cm-1. Temperature-dependent thermodynamic functions, and thermochemistry of dissociation, are computed from the spectroscopic data. The ideal-gas enthalpy of formation is ΔfH298.15o(PtH) = (449.1 ± 4.5) kJ mol-1 (uncertainties expanded by k = 2). The experimental data are reinterpreted, using a somewhat speculative procedure, to yield the bond length Re = (1.5199 ± 0.0006) Å.
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Affiliation(s)
- Karl K Irikura
- Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
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4
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Saly E, Ferenc D, Mátyus E. Pre-Born–Oppenheimer energies, leading-order relativistic and QED corrections for electronically excited states of molecular hydrogen. Mol Phys 2023. [DOI: 10.1080/00268976.2022.2163714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Eszter Saly
- Institute of Chemistry, ELTE, Eötvös Loránd University, Budapest, Hungary
| | - Dávid Ferenc
- Institute of Chemistry, ELTE, Eötvös Loránd University, Budapest, Hungary
| | - Edit Mátyus
- Institute of Chemistry, ELTE, Eötvös Loránd University, Budapest, Hungary
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5
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Munro-Laylim P, Dzuba V, Flambaum V. Effects of the long-range neutrino-mediated force in atomic phenomena. Mol Phys 2022. [DOI: 10.1080/00268976.2022.2160385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
| | - Vladimir Dzuba
- School of Physics, University of New South Wales, Sydney, Australia
| | - Victor Flambaum
- School of Physics, University of New South Wales, Sydney, Australia
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6
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Commissioning of the HITRAP Cooling Trap with Offline Ions. ATOMS 2022. [DOI: 10.3390/atoms10040142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Highly charged heavy ions at rest offer a wide spectrum of precision measurements. The GSI Helmholtzzentrum für Schwerionenforschung GmbH is able to deliver ions up to U92+. As the production of these heavy, highly charged ions requires high kinetic energies, it is necessary to decelerate these ions for ultimate precision. The broad energy distribution, which results from the deceleration in the HITRAP linear decelerator, needs to be reduced to allow for further transportation and experiments. The HITRAP cooling trap is designed to cool, i.e., reduce, this energy spread by utilizing electron cooling. The commissioning of this trap is done with Ar16+-ions from a local EBIT ion source. By analyzing the signal of stored ions after ejection, properties such as ion lifetime, charge exchange, and ion motions can be observed. Here, we provide an overview of the recent results of the commissioning process and discuss future experiments.
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7
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Qiu LQ, Yao X, Zhang YK, Li HR, He LN. Advancements and Challenges in Reductive Conversion of Carbon Dioxide via Thermo-/Photocatalysis. J Org Chem 2022; 88:4942-4964. [PMID: 36342846 DOI: 10.1021/acs.joc.2c02179] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Carbon dioxide (CO2) is the major greenhouse gas and also an abundant and renewable carbon resource. Therefore, its chemical conversion and utilization are of great attraction for sustainable development. Especially, reductive conversion of CO2 with energy input has become a current hotspot due to its ability to access fuels and various important chemicals. Nowadays, the controllable CO2 hydrogenation to formic acid and alcohols using sustainable H2 resources has been regarded as an appealing solution to hydrogen storage and CO2 accumulation. In addition, photocatalytic CO2 reduction to CO also provides a potential way to utilize this greenhouse gas efficiently. Besides direct CO2 hydrogenation, CO2 reductive functionalization integrates CO2 reduction with subsequent C-X (X = N, S, C, O) bond formation and indirect transformation strategies, enlarging the diverse products derived from CO2 and promoting CO2 reductive conversion into a new stage. In this Perspective, the progress and challenges of CO2 reductive conversion, including hydrogenation, reductive functionalization, photocatalytic reduction, and photocatalytic reductive functionalization are summarized and discussed along with the key issues and future trends/directions in this field. We hope this Perspective can evoke intense interest and inspire much innovation in the promise of CO2 valorization.
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Affiliation(s)
- Li-Qi Qiu
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Xiangyang Yao
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Yong-Kang Zhang
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Hong-Ru Li
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
- College of Pharmacy, Nankai University, Tianjin 300353, China
| | - Liang-Nian He
- State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
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8
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Siłkowski M, Pachucki K. Born–Oppenheimer potentials for Π, Δ, and Φ states of the hydrogen molecule. Mol Phys 2022. [DOI: 10.1080/00268976.2022.2062471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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9
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Poirier B, Jerke J. Full-dimensional Schrödinger wavefunction calculations using tensors and quantum computers: the Cartesian component-separated approach. Phys Chem Chem Phys 2022; 24:4437-4454. [PMID: 35113096 DOI: 10.1039/d1cp02036f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Traditional methods in quantum chemistry rely on Hartree-Fock-based Slater-determinant (SD) representations, whose underlying zeroth-order picture assumes separability by particle. Here, we explore a radically different approach, based on separability by Cartesian component, rather than by particle [J. Jerke and B. Poirier, J. Chem. Phys., 2018, 148, 104101]. The approach appears to be very well suited for 3D grid-based methods in quantum chemistry, and thereby also for so-called "first-quantized" quantum computing. We first present an overview of the approach as implemented on classical computers, including numerical results that justify performance claims. In particular, we perform numerical calculations with four explicit electrons that are equivalent to full-CI matrix diagonalization with nearly 1015 SDs. We then present an implementation for quantum computers for which the number of quantum gates (and to a lesser extent, the number of qubits) can be dramatically reduced, in comparison with other quantum circuitry that has been envisioned for implementing first-quantized "quantum computational chemistry" (QCC).
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Affiliation(s)
- Bill Poirier
- Department of Chemistry and Biochemistry and Department of Physics, Texas Tech University, P.O. Box 41061, Lubbock, Texas 79409-1061, USA.
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10
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Neutral Dissociation of Pyridine Evoked by Irradiation of Ionized Atomic and Molecular Hydrogen Beams. Int J Mol Sci 2021; 23:ijms23010205. [PMID: 35008633 PMCID: PMC8745593 DOI: 10.3390/ijms23010205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 12/19/2021] [Accepted: 12/22/2021] [Indexed: 11/17/2022] Open
Abstract
The interactions of ions with molecules and the determination of their dissociation patterns are challenging endeavors of fundamental importance for theoretical and experimental science. In particular, the investigations on bond-breaking and new bond-forming processes triggered by the ionic impact may shed light on the stellar wind interaction with interstellar media, ionic beam irradiations of the living cells, ion-track nanotechnology, radiation hardness analysis of materials, and focused ion beam etching, deposition, and lithography. Due to its vital role in the natural environment, the pyridine molecule has become the subject of both basic and applied research in recent years. Therefore, dissociation of the gas phase pyridine (C5H5N) into neutral excited atomic and molecular fragments following protons (H+) and dihydrogen cations (H2+) impact has been investigated experimentally in the 5–1000 eV energy range. The collision-induced emission spectroscopy has been exploited to detect luminescence in the wavelength range from 190 to 520 nm at the different kinetic energies of both cations. High-resolution optical fragmentation spectra reveal emission bands due to the CH(A2Δ→X2Πr; B2Σ+→X2Πr; C2Σ+→X2Πr) and CN(B2Σ+→X2Σ+) transitions as well as atomic H and C lines. Their spectral line shapes and qualitative band intensities are examined in detail. The analysis shows that the H2+ irradiation enhances pyridine ring fragmentation and creates various fragments more pronounced than H+ cations. The plausible collisional processes and fragmentation pathways leading to the identified products are discussed and compared with the latest results obtained in cation-induced fragmentation of pyridine.
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11
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Lai KF, Salumbides EJ, Beyer M, Ubachs W. Precision measurement of quasi-bound resonances in H2 and the H + H scattering length. Mol Phys 2021. [DOI: 10.1080/00268976.2021.2018063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- K.-F. Lai
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit, Amsterdam, Netherlands
| | - E. J. Salumbides
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit, Amsterdam, Netherlands
| | - M. Beyer
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit, Amsterdam, Netherlands
| | - W. Ubachs
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit, Amsterdam, Netherlands
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12
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Rayment MH, Hogan SD. Quantum-state-dependent decay rates of electrostatically trapped Rydberg NO molecules. Phys Chem Chem Phys 2021; 23:18806-18822. [PMID: 34612419 PMCID: PMC8900602 DOI: 10.1039/d1cp01930a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nitric oxide (NO) molecules travelling in pulsed supersonic beams have been prepared in long-lived Rydberg-Stark states by resonance-enhanced two-colour two-photon excitation from the X 2Π1/2 (v'' = 0, J'' = 3/2) ground state, through the A 2Σ+ (v' = 0, N' = 0, J' = 1/2) intermediate state. These excited molecules were decelerated from 795 ms-1 to rest in the laboratory-fixed frame of reference, in the travelling electric traps of a transmission-line Rydberg-Stark decelerator. The decelerator was operated at 30 K to minimise effects of blackbody radiation on the molecules during deceleration and trapping. The molecules were electrostatically trapped for times of up to 1 ms, and detected in situ by pulsed electric field ionisation. Measurements of the rate of decay from the trap were performed for states with principal quantum numbers between n = 32 and 50, in Rydberg series converging to the N+= 0, 1, and 2 rotational states of NO+. For the range of Rydberg states studied, the measured decay times of between 200 μs and 400 μs were generally observed to reduce as the value of n was increased. For some particular values of n deviations from this trend were seen. These observations are interpreted, with the aid of numerical calculations, to arise as a result of contributions to the decay rates, on the order of 1 kHz, from rotational and vibrational channel interactions. These results shed new light on the role of weak intramolecular interactions on the slow decay of long-lived Rydberg states in NO.
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Affiliation(s)
- M H Rayment
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK.
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13
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Yarman T, Zaim N, Arik M, Kholmetskii A, Yarman O. Diatomic molecules’ enigmatic constancy as the product of their dissociation energy and interatomic distance. Mol Phys 2021. [DOI: 10.1080/00268976.2020.1871087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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14
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Kovalenko A, Roučka Š, Tran TD, Rednyk S, Plašil R, Dohnal P, Glosík J. The reaction of O +( 4S) ions with H 2, HD, and D 2 at low temperatures: Experimental study of the isotope effect. J Chem Phys 2021; 154:094301. [PMID: 33685178 DOI: 10.1063/5.0036049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The reactions of the O+ ions in the 4S electronic ground state with D2 and HD were studied in a cryogenic 22-pole radio-frequency ion trap in the temperature range of 15 K-300 K. The obtained reaction rate coefficients for both reactions are, considering the experimental errors, nearly independent of temperature and close to the values of the corresponding Langevin collisional reaction rate coefficients. The obtained branching ratios for the production of OH+ and OD+ in the reaction of O+(4S) with HD do not change significantly with temperature and are consistent with the results obtained at higher collisional energies by other groups. Particular attention was given to ensure that the O+ ions in the trap are in the ground electronic state.
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Affiliation(s)
- A Kovalenko
- Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 180 00 Prague, Czech Republic
| | - Š Roučka
- Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 180 00 Prague, Czech Republic
| | - T D Tran
- Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 180 00 Prague, Czech Republic
| | - S Rednyk
- Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 180 00 Prague, Czech Republic
| | - R Plašil
- Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 180 00 Prague, Czech Republic
| | - P Dohnal
- Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 180 00 Prague, Czech Republic
| | - J Glosík
- Department of Surface and Plasma Science, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, 180 00 Prague, Czech Republic
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15
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Bornhauser P, Beck M, Zhang Q, Knopp G, Marquardt R, Gourlaouen C, Radi PP. Accurate ground state potential of Cu 2 up to the dissociation limit by perturbation assisted double-resonant four-wave mixing. J Chem Phys 2020; 153:244305. [PMID: 33380116 DOI: 10.1063/5.0028908] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Perturbation facilitated double-resonant four-wave mixing is applied to access high-lying vibrational levels of the X 1Σg + (0g +) ground state of Cu2. Rotationally resolved transitions up to v″ = 102 are measured. The highest observed level is at 98% of the dissociation energy. The range and accuracy of previous measurements are significantly extended. By applying the near dissociation equation developed by Le Roy [R. J. Le Roy, J. Quant. Spectrosc. Radiat. Transfer 186, 197 (2017)], a dissociation energy of De = 16 270(7) hc cm-1 is determined, and an accurate potential energy function for the X 1Σg + (0g +) ground state is obtained. Molecular constants are determined from the measured transitions and by solving the radial Schrödinger equation using this function and are compared with results from earlier measurements. In addition, benchmark multi-reference configuration interaction computations are performed using the Douglas-Kroll-Hess Hamiltonian and the appropriate basis of augmented valence quadruple ζ type. Coupled-cluster single, double, and perturbative triple calculations were performed for comparison.
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Affiliation(s)
- P Bornhauser
- Paul Scherrer Institute, Photon Science Department, CH-5232 Villigen, Switzerland
| | - M Beck
- Paul Scherrer Institute, Photon Science Department, CH-5232 Villigen, Switzerland
| | - Q Zhang
- Paul Scherrer Institute, Photon Science Department, CH-5232 Villigen, Switzerland
| | - G Knopp
- Paul Scherrer Institute, Photon Science Department, CH-5232 Villigen, Switzerland
| | - R Marquardt
- Laboratoire de Chimie Quantique, Institut de Chimie, UMR 7177, Université de Strasbourg/CNRS, 4, Rue Blaise Pascal - CS90032, 67081 Strasbourg Cedex, France
| | - C Gourlaouen
- Laboratoire de Chimie Quantique, Institut de Chimie, UMR 7177, Université de Strasbourg/CNRS, 4, Rue Blaise Pascal - CS90032, 67081 Strasbourg Cedex, France
| | - P P Radi
- Paul Scherrer Institute, Photon Science Department, CH-5232 Villigen, Switzerland
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16
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Quinn MS, Nauta K, Kable SH. Disentangling the H2E, F(1Σg+) (v′=0−18)←X(1Σg+)(v″=3−9)(2+1) REMPI spectrum via 2D velocity-mapped imaging. Mol Phys 2020. [DOI: 10.1080/00268976.2020.1836412] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- Mitchell S. Quinn
- The University of New South Wales at Sydney, Kensington, NSW, Australia
| | - Klaas Nauta
- The University of New South Wales at Sydney, Kensington, NSW, Australia
| | - Scott H. Kable
- The University of New South Wales at Sydney, Kensington, NSW, Australia
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17
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Lai KF, Hermann V, Trivikram TM, Diouf M, Schlösser M, Ubachs W, Salumbides EJ. Precision measurement of the fundamental vibrational frequencies of tritium-bearing hydrogen molecules: T 2, DT, HT. Phys Chem Chem Phys 2020; 22:8973-8987. [PMID: 32292981 DOI: 10.1039/d0cp00596g] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
High-resolution coherent Raman spectroscopic measurements of all three tritium-containing molecular hydrogen isotopologues T2, DT and HT were performed to determine the ground electronic state fundamental Q-branch (v = 0 → 1, ΔJ = 0) transition frequencies at accuracies of 0.0005 cm-1. An over hundred-fold improvement in accuracy over previous experiments allows the comparison with the latest ab initio calculations in the framework of non-adiabatic perturbation theory including nonrelativisitic, relativisitic and QED contributions. Excellent agreement is found between experiment and theory, thus providing a verification of the validity of the NAPT-framework for these tritiated species. While the transition frequencies were corrected for ac-Stark shifts, the contributions of non-resonant background as well as quantum interference effects between resonant features in the nonlinear spectroscopy were quantitatively investigated, also leading to corrections to the transition frequencies. Methods of saturated CARS with the observation of Lamb dips, as well as the use of continuous-wave radiation for the Stokes frequency were explored, that might pave the way for future higher-accuracy CARS measurements.
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Affiliation(s)
- K-F Lai
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
| | - V Hermann
- Tritium Laboratory Karlsruhe, Institute of Nuclear Physics, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - T M Trivikram
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
| | - M Diouf
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
| | - M Schlösser
- Tritium Laboratory Karlsruhe, Institute of Nuclear Physics, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - W Ubachs
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
| | - E J Salumbides
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
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18
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Trivikram TM, Salumbides EJ, Jungen C, Ubachs W. Excitation of H 2 at large internuclear separation: outer well states and continuum resonances. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1599457] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- T. M. Trivikram
- Department of Physics and Astronomy, and LaserLaB, Vrije Universiteit, Amsterdam, The Netherlands
| | - E. J. Salumbides
- Department of Physics and Astronomy, and LaserLaB, Vrije Universiteit, Amsterdam, The Netherlands
| | - Ch. Jungen
- Department of Physics and Astronomy, University College London, London, United Kingdom
| | - W. Ubachs
- Department of Physics and Astronomy, and LaserLaB, Vrije Universiteit, Amsterdam, The Netherlands
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19
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Beyer M, Hölsch N, Hussels J, Cheng CF, Salumbides EJ, Eikema KSE, Ubachs W, Jungen C, Merkt F. Determination of the Interval between the Ground States of Para- and Ortho-H_{2}. PHYSICAL REVIEW LETTERS 2019; 123:163002. [PMID: 31702363 DOI: 10.1103/physrevlett.123.163002] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Indexed: 06/10/2023]
Abstract
Nuclear-spin-symmetry conservation makes the observation of transitions between quantum states of ortho- and para-H_{2} extremely challenging. Consequently, the energy-level structure of H_{2} derived from experiment consists of two disjoint sets of level energies, one for para-H_{2} and the other for ortho-H_{2}. We use a new measurement of the ionization energy of para-H_{2} [E_{I}(H_{2})/(hc)=124 417.491 098(31) cm^{-1}] to determine the energy separation [118.486 770(50) cm^{-1}] between the ground states of para- and ortho-H_{2} and thus link the energy-level structure of the two nuclear-spin isomers of this fundamental molecule. Comparison with recent theoretical results [M. Puchalski et al., Phys. Rev. Lett. 122, 103003 (2019)PRLTAO0031-900710.1103/PhysRevLett.122.103003] enables the derivation of an upper bound of 1.5 MHz for a hypothetical global shift of the energy-level structure of ortho-H_{2} with respect to that of para-H_{2}.
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Affiliation(s)
- M Beyer
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - N Hölsch
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - J Hussels
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - C-F Cheng
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - E J Salumbides
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - K S E Eikema
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - W Ubachs
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - Ch Jungen
- Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
| | - F Merkt
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
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20
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Setzer WJ, de Magalhaes A, Morgan TJ. Spectrum of Field-Ionized Triplet Gerade Rydberg States of H 2 and Comparison to Multichannel Quantum-Defect Theory. J Phys Chem A 2019; 123:3535-3542. [PMID: 30943033 DOI: 10.1021/acs.jpca.9b01445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A spectrum of field-ionized triplet Rydberg states of gerade symmetry H2 has been measured, excited from the υ″ = 0, N″ = 1-3 rovibrational levels of the metastable c3Πu-2pπ state in a 6 keV fast molecular beam. The field-ionized spectrum is kinetic energy labeled in order to separate it from the well-studied υ+ ≥ 1 autoionization spectrum. The spectrum consists of both ns and nd Rydberg series with n between 10 and 28 converging to the υ+ = 0, N+ = 1-3 levels of the X+ 2Σg+ ground state of H2+. Transitions with changes in vibration and/or rotation are also identified. The spectral positions of 59 transitions in the field ionization spectrum are identified and assigned quantum numbers using the predictions of multichannel quantum-defect theory (MQDT). The transition energies and subsequent effective quantum defects are compared between the experiment and theory. Most of the observed transitions, within the experimental uncertainty of 0.2 cm-1, agree with the energies predicted by MQDT.
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Affiliation(s)
- W J Setzer
- Department of Physics , Wesleyan University , Middletown , Connecticut 06459 , United States
| | - A de Magalhaes
- Department of Physics , Wesleyan University , Middletown , Connecticut 06459 , United States
| | - T J Morgan
- Department of Physics , Wesleyan University , Middletown , Connecticut 06459 , United States
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21
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Puchalski M, Komasa J, Czachorowski P, Pachucki K. Nonadiabatic QED Correction to the Dissociation Energy of the Hydrogen Molecule. PHYSICAL REVIEW LETTERS 2019; 122:103003. [PMID: 30932623 DOI: 10.1103/physrevlett.122.103003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Indexed: 06/09/2023]
Abstract
The quantum electrodynamic correction to the energy of the hydrogen molecule has been evaluated without expansion in the electron-proton mass ratio. The obtained results significantly improve the accuracy of theoretical predictions reaching the level of 1 MHz for the dissociation energy, in very good agreement with the parallel measurement [Hölsch et al., Phys. Rev. Lett. 122, 103002 (2019)PRLTAO0031-900710.1103/PhysRevLett.122.103002]. Molecular hydrogen has thus become a cornerstone of ultraprecise quantum chemistry, which opens perspectives for determination of fundamental physical constants from its spectra.
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Affiliation(s)
- Mariusz Puchalski
- Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznań, Poland
| | - Jacek Komasa
- Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznań, Poland
| | - Paweł Czachorowski
- Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Krzysztof Pachucki
- Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
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22
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Hölsch N, Beyer M, Salumbides EJ, Eikema KSE, Ubachs W, Jungen C, Merkt F. Benchmarking Theory with an Improved Measurement of the Ionization and Dissociation Energies of H_{2}. PHYSICAL REVIEW LETTERS 2019; 122:103002. [PMID: 30932670 DOI: 10.1103/physrevlett.122.103002] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 01/29/2019] [Indexed: 06/09/2023]
Abstract
The dissociation energy of H_{2} represents a benchmark quantity to test the accuracy of first-principles calculations. We present a new measurement of the energy interval between the EF ^{1}Σ_{g}^{+}(v=0,N=1) state and the 54p1_{1} Rydberg state of H_{2}. When combined with previously determined intervals, this new measurement leads to an improved value of the dissociation energy D_{0}^{N=1} of ortho-H_{2} that has, for the first time, reached a level of uncertainty that is 3 times smaller than the contribution of about 1 MHz resulting from the finite size of the proton. The new result of 35 999.582 834(11) cm^{-1} is in remarkable agreement with the theoretical result of 35 999.582 820(26) cm^{-1} obtained in calculations including high-order relativistic and quantum-electrodynamics corrections, as reported in the following Letter [M. Puchalski, J. Komasa, P. Czachorowski, and K. Pachucki, Phys. Rev. Lett. 122, 103003 (2019)PRLTAO0031-900710.1103/PhysRevLett.122.103003]. This agreement resolves a recent discrepancy between experiment and theory that had hindered a possible use of the dissociation energy of H_{2} in the context of the current controversy on the charge radius of the proton.
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Affiliation(s)
- Nicolas Hölsch
- Laboratorium für Physikalische Chemie, ETH-Zürich, 8093 Zürich, Switzerland
| | - Maximilian Beyer
- Laboratorium für Physikalische Chemie, ETH-Zürich, 8093 Zürich, Switzerland
| | - Edcel J Salumbides
- LaserLaB, Department of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Kjeld S E Eikema
- LaserLaB, Department of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Wim Ubachs
- LaserLaB, Department of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Christian Jungen
- Department of Physics and Astronomy, University College London, London, WC1E 6BT United Kingdom
| | - Frédéric Merkt
- Laboratorium für Physikalische Chemie, ETH-Zürich, 8093 Zürich, Switzerland
- LaserLaB, Department of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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23
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Gutsev GL, Bozhenko KV, Gutsev LG, Utenyshev AN, Aldoshin SM. Hydrogenation of 3d-metal oxide clusters: Effects on the structure and magnetic properties. J Comput Chem 2019; 40:562-571. [PMID: 30549078 DOI: 10.1002/jcc.25739] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 10/05/2018] [Accepted: 10/05/2018] [Indexed: 11/08/2022]
Abstract
The geometrical structures and properties of the M8 O12 , M8 O12 H8 , and M8 O12 H12 clusters are explored using density functional theory with the generalized gradient approximation for all 3d-metals M from Sc to Zn. It is found that the geometries and total spin magnetic moments of the clusters depended strongly on the 3d-atom type and the hydrogenation extent. More than the half of all of the 30 clusters had singlet lowest total energy states, which could be described as either nonmagnetic or antiferromagnetic. Hydrogenation increases the total spin magnetic moments of the M8 O12 H12 clusters when MMnNi, which become larger by four Bohr magneton than those of the corresponding unary clusters M8 . Hydrogenation substantially affects such properties as polarizability, forbidden band gaps, and dipole moments. Collective superexchange where the local total spin magnetic moments of two atom squads are coupled antiparallel was observed in antiferromagnetic singlet states of Fe8 O12 H8 and Co8 O12 H8 , whereas the lowest total energy states of their neighbors Mn8 O12 H8 and Ni8 O12 H8 are ferrimagnetic and ferromagnetic, respectively. Hydrogenation leads to a decrease in the average binding energy per atom when moving across the 3d-metal atom series. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- G L Gutsev
- Department of Physics, Florida A&M University, Tallahassee, Florida, 32307
| | - K V Bozhenko
- Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432, Moscow Region, Russia.,Рeoples' Friendship University of Russia (RUDN University), Moscow 117198, Russian Federation
| | - L G Gutsev
- Department of Physics, Virginia Commonwealth University, Richmond, Virginia, 23284
| | - A N Utenyshev
- Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432, Moscow Region, Russia
| | - S M Aldoshin
- Institute of Problems of Chemical Physics, Russian Academy of Sciences, Chernogolovka 142432, Moscow Region, Russia
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24
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Mátyus E. Non-adiabatic mass-correction functions and rovibrational states of 4 He 2 + ( X 2 Σ u + ). J Chem Phys 2018; 149:194112. [PMID: 30466288 DOI: 10.1063/1.5050403] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The mass-correction functions in the second-order non-adiabatic Hamiltonian are computed for the 4 He 2 + molecular ion using the variational method, floating explicitly correlated Gaussian functions, and a general coordinate-transformation formalism. When non-adiabatic rovibrational energy levels are computed using these (coordinate-dependent) mass-correction functions and a highly accurate potential energy and diagonal Born-Oppenheimer correction curve, significantly improved theoretical results are obtained for the nine rotational and two rovibrational intervals known from high-resolution spectroscopy experiments.
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Affiliation(s)
- Edit Mátyus
- Institute of Chemistry, Eötvös Loránd University, Pázmány Péter Sétány 1/A, Budapest H-1117, Hungary
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25
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Jansen P, Semeria L, Merkt F. Fundamental vibration frequency and rotational structure of the first excited vibrational level of the molecular helium ion ( He 2 + ). J Chem Phys 2018; 149:154302. [PMID: 30342452 DOI: 10.1063/1.5051089] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The term values of the rotational levels of the first excited vibrational state of the electronic ground state of He 2 + with a rotational quantum number N + ≤ 13 have been determined with an accuracy of 1.2 × 10-3 cm-1 (∼35 MHz) by multichannel-quantum-defect-theory-assisted Rydberg spectroscopy of metastable He2. Comparison of the experimental term values with the most accurate ab initio results for He 2 + available in the literature [W.-C. Tung, M. Pavanello, and L. Adamowicz, J. Chem. Phys. 136, 104309 (2012)] reveals inconsistencies between the theoretical and experimental results that increase with increasing rotational quantum numbers. The fundamental vibrational wavenumber of He 2 + was determined to be 1628.3832(12) cm-1 by fitting effective molecular constants to the obtained term values.
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Affiliation(s)
- Paul Jansen
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Luca Semeria
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Frédéric Merkt
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
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26
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Wang L, Yan ZC. Relativistic corrections to the ground states of HD and D 2 calculated without using the Born-Oppenheimer approximation. Phys Chem Chem Phys 2018; 20:23948-23953. [PMID: 30209496 DOI: 10.1039/c8cp04586k] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Schrödinger equation for the ground states of the hydrogen molecules HD and D2 is solved variationally by treating the constituent particles of HD or D2 on the same footing without assuming the Born-Oppenheimer approximation. The variational basis sets are constructed using Hylleraas coordinates that are traditionally adopted for few-electron atomic systems. The nonrelativistic energy eigenvalues are converged to the level of 10-6 cm-1. The leading-order relativistic corrections, including relativistic recoil terms, are calculated rigorously. Together with the higher-order relativistic and quantum electrodynamic corrections obtained by the Pachucki's group [Phys. Rev. A., 2017, 95, 052506; Phys. Rev. Lett., 2018, 120, 153001], we determine the dissociation energy of D2 to be 36748.36240(28) cm-1, which agrees with the recent experimental result of Liu et al. [J. Chem. Phys., 2010, 132, 154301] 36748.36286(68) cm-1. For HD, the dissociation energy determined by us is 36405.78252(27) cm-1, which deviates from the most accurate experimental result of Sprecher et al. [J. Chem. Phys., 2010, 133, 111102] 36405.78366(36) cm-1 by about 2σ.
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Affiliation(s)
- Liming Wang
- Department of Physics, Henan Normal University, 453007, Xinxiang, Henan, China.
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27
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Puchalski M, Spyszkiewicz A, Komasa J, Pachucki K. Nonadiabatic Relativistic Correction to the Dissociation Energy of H_{2}, D_{2}, and HD. PHYSICAL REVIEW LETTERS 2018; 121:073001. [PMID: 30169069 DOI: 10.1103/physrevlett.121.073001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Indexed: 06/08/2023]
Abstract
The relativistic correction to the dissociation energy of H_{2}, D_{2}, and HD molecules has been accurately calculated without expansion in the small electron-nucleus mass ratio. The obtained results indicate the significance of nonadiabatic effects and resolve the discrepancy of theoretical predictions with recent experimental values for H_{2} and D_{2}. While the theoretical accuracy is now significantly improved and is higher than the experimental one, we observe about 3σ discrepancy for the dissociation energy of HD, which requires further investigation.
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Affiliation(s)
- Mariusz Puchalski
- Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznań, Poland
| | - Anna Spyszkiewicz
- Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznań, Poland
| | - Jacek Komasa
- Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznań, Poland
| | - Krzysztof Pachucki
- Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
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28
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Bello RY, Canton SE, Jelovina D, Bozek JD, Rude B, Smirnova O, Ivanov MY, Palacios A, Martín F. Reconstruction of the time-dependent electronic wave packet arising from molecular autoionization. SCIENCE ADVANCES 2018; 4:eaat3962. [PMID: 30151427 PMCID: PMC6108568 DOI: 10.1126/sciadv.aat3962] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 07/18/2018] [Indexed: 06/08/2023]
Abstract
Autoionizing resonances are paradigmatic examples of two-path wave interferences between direct photoionization, which takes a few attoseconds, and ionization via quasi-bound states, which takes much longer. Time-resolving the evolution of these interferences has been a long-standing goal, achieved recently in the helium atom owing to progress in attosecond technologies. However, already for the hydrogen molecule, similar time imaging has remained beyond reach due to the complex interplay between fast nuclear and electronic motions. We show how vibrationally resolved photoelectron spectra of H2 allow one to reconstruct the associated subfemtosecond autoionization dynamics by using the ultrafast nuclear dynamics as an internal clock, thus forgoing ultrashort pulses. Our procedure should be general for autoionization dynamics in molecules containing light nuclei, which are ubiquitous in chemistry and biology.
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Affiliation(s)
- Roger Y. Bello
- Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Sophie E. Canton
- Extreme Light Infrastructure Attosecond Light Pulse Source, ELI-HU Non-Profit Ltd., Dugonics ter 13, Szeged 6720, Hungary
- Attosecond Science Group, Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, D-22607 Hamburg, Germany
| | - Denis Jelovina
- Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - John D. Bozek
- Synchrotron SOLEIL, L’Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France
| | - Bruce Rude
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Olga Smirnova
- Max-Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Straße 2A, D-12489 Berlin, Germany
- Technische Universität Berlin, Ernst-Ruska-Gebäude, Hardenbergstr. 36 A, 10623 Berlin, Germany
| | - Mikhail Y. Ivanov
- Max-Born Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Straße 2A, D-12489 Berlin, Germany
- Department of Physics, Imperial College London, South Kensington Campus, SW72AZ London, UK
- Institute of Physics, Humboldt University Berlin, Newtonstrasse 15, 12489 Berlin, Germany
| | - Alicia Palacios
- Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Institute for Advanced Research in Chemical Sciences, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Fernando Martín
- Departamento de Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Instituto Madrileño de Estudios Avanzados en Nanociencia, Cantoblanco, 28049 Madrid, Spain
- Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain
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29
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Cheng CF, Hussels J, Niu M, Bethlem HL, Eikema KSE, Salumbides EJ, Ubachs W, Beyer M, Hölsch N, Agner JA, Merkt F, Tao LG, Hu SM, Jungen C. Dissociation Energy of the Hydrogen Molecule at 10^{-9} Accuracy. PHYSICAL REVIEW LETTERS 2018; 121:013001. [PMID: 30028156 DOI: 10.1103/physrevlett.121.013001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Indexed: 06/08/2023]
Abstract
The ionization energy of ortho-H_{2} has been determined to be E_{I}^{o}(H_{2})/(hc)=124 357.238 062(25) cm^{-1} from measurements of the GK(1,1)-X(0,1) interval by Doppler-free, two-photon spectroscopy using a narrow band 179-nm laser source and the ionization energy of the GK(1,1) state by continuous-wave, near-infrared laser spectroscopy. E_{I}^{o}(H_{2}) was used to derive the dissociation energy of H_{2}, D_{0}^{N=1}(H_{2}), at 35 999.582 894(25) cm^{-1} with a precision that is more than one order of magnitude better than all previous results. The new result challenges calculations of this quantity and represents a benchmark value for future relativistic and QED calculations of molecular energies.
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Affiliation(s)
- C-F Cheng
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - J Hussels
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - M Niu
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - H L Bethlem
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - K S E Eikema
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - E J Salumbides
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - W Ubachs
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - M Beyer
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - N Hölsch
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - J A Agner
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - F Merkt
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - L-G Tao
- Hefei National Laboratory for Physical Sciences at Microscale, iChem center, University of Science and Technology China, Hefei, 230026 China
| | - S-M Hu
- Hefei National Laboratory for Physical Sciences at Microscale, iChem center, University of Science and Technology China, Hefei, 230026 China
| | - Ch Jungen
- Laboratoire Aimé Cotton du CNRS, Bâtiment 505, Université de Paris-Sud, F-91405 Orsay, France and Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
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30
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Ormond TK, Baraban JH, Porterfield JP, Scheer AM, Hemberger P, Troy TP, Ahmed M, Nimlos MR, Robichaud DJ, Daily JW, Ellison GB. Thermal Decompositions of the Lignin Model Compounds: Salicylaldehyde and Catechol. J Phys Chem A 2018; 122:5911-5924. [DOI: 10.1021/acs.jpca.8b03201] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Thomas K. Ormond
- National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, United States
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Joshua H. Baraban
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Jessica P. Porterfield
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
| | - Adam M. Scheer
- Combustion Research Facility, Sandia National Laboratory, PO Box 969, Livermore, California 94551-0969, United States
| | - Patrick Hemberger
- Laboratory for Femtochemistry and Synchrotron Radiation, Paul Scherrer Institute, CH-5234 Villigen-PSI, Switzerland
| | - Tyler P. Troy
- Chemical Sciences Division, Lawrence Berkeley National Laboratories, Berkeley, California 94720, United States
| | - Musahid Ahmed
- Chemical Sciences Division, Lawrence Berkeley National Laboratories, Berkeley, California 94720, United States
| | - Mark R. Nimlos
- National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, United States
| | - David J. Robichaud
- National Renewable Energy Laboratory, 15013 Denver West Parkway, Golden, Colorado 80401, United States
| | - John W. Daily
- Center for Combustion and Environmental Research, Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309-0427, United States
| | - G. Barney Ellison
- Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado 80309-0215, United States
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31
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Trivikram TM, Schlösser M, Ubachs W, Salumbides EJ. Relativistic and QED Effects in the Fundamental Vibration of T_{2}. PHYSICAL REVIEW LETTERS 2018; 120:163002. [PMID: 29756935 DOI: 10.1103/physrevlett.120.163002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Indexed: 06/08/2023]
Abstract
The hydrogen molecule has become a test ground for quantum electrodynamical calculations in molecules. Expanding beyond studies on stable hydrogenic species to the heavier radioactive tritium-bearing molecules, we report on a measurement of the fundamental T_{2} vibrational splitting (v=0→1) for J=0-5 rotational levels. Precision frequency metrology is performed with high-resolution coherent anti-Stokes Raman spectroscopy at an experimental uncertainty of 10-12 MHz, where sub-Doppler saturation features are exploited for the strongest transition. The achieved accuracy corresponds to a 50-fold improvement over a previous measurement, and it allows for the extraction of relativistic and QED contributions to T_{2} transition energies.
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Affiliation(s)
- T Madhu Trivikram
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - M Schlösser
- Tritium Laboratory Karlsruhe, Institute of Technical Physics, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - W Ubachs
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - E J Salumbides
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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32
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Cozijn FMJ, Dupré P, Salumbides EJ, Eikema KSE, Ubachs W. Sub-Doppler Frequency Metrology in HD for Tests of Fundamental Physics. PHYSICAL REVIEW LETTERS 2018; 120:153002. [PMID: 29756874 DOI: 10.1103/physrevlett.120.153002] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Indexed: 06/08/2023]
Abstract
Weak transitions in the (2,0) overtone band of the hydrogen deuteride molecule at λ=1.38 μm were measured in saturated absorption using the technique of noise-immune cavity-enhanced optical heterodyne molecular spectroscopy. Narrow Doppler-free lines were interrogated with a spectroscopy laser locked to a frequency comb laser referenced to an atomic clock to yield transition frequencies [R(1)=217105181895(20) kHz; R(2)=219042856621(28) kHz; R(3)=220704304951(28) kHz] at three orders of magnitude improved accuracy. These benchmark values provide a test of QED in the smallest neutral molecule, and they open up an avenue to resolve the proton radius puzzle, as well as constrain putative fifth forces and extra dimensions.
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Affiliation(s)
- F M J Cozijn
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - P Dupré
- Laboratoire de Physico-Chimie de l'Atmosphère, Université du Littoral Côte d'Opale, 189A Avenue Maurice Schumann, 59140 Dunkerque, France
| | - E J Salumbides
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - K S E Eikema
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - W Ubachs
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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33
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Fichet S. Quantum Forces from Dark Matter and Where to Find Them. PHYSICAL REVIEW LETTERS 2018; 120:131801. [PMID: 29694222 DOI: 10.1103/physrevlett.120.131801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 01/05/2018] [Indexed: 06/08/2023]
Abstract
We observe that sub-GeV dark matter (DM) induces Casimir-Polder forces between nucleons that can be accessed by experiments from nuclear to molecular scales. We calculate the nucleon-nucleon potentials arising in the DM effective theory and note that their main features are fixed by dimensional analysis and the optical theorem. Molecular spectroscopy and neutron scattering turn out be DM search experiments and are found to be complementary to nucleon-based DM direct detection. Existing data set limits on DM with mass up to ∼3-50 MeV and with effective interaction up to the O(10-100) MeV scale, constraining a region typically difficult to reach for other experiments.
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Affiliation(s)
- Sylvain Fichet
- ICTP-SAIFR and IFT-UNESP, Rua Dr. Bento Teobaldo Ferraz 271, São Paulo, Brazil
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34
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Pachucki K, Komasa J. Nonadiabatic rotational states of the hydrogen molecule. Phys Chem Chem Phys 2018; 20:247-255. [PMID: 29200217 DOI: 10.1039/c7cp06516g] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
We present a new computational method for the determination of energy levels in four-particle systems like H2, HD, and HeH+ using explicitly correlated exponential basis functions and analytic integration formulas. In solving the Schrödinger equation, no adiabatic separation of the nuclear and electronic degrees of freedom is introduced. We provide formulas for the coupling between the rotational and electronic angular momenta, which enable calculations of arbitrary rotationally excited energy levels. To illustrate the high numerical efficiency of the method, we present the results for various states of the hydrogen molecule. The relative accuracy to which we determined the nonrelativistic energy reached the level of 10-12-10-13, which corresponds to an uncertainty of 10-7-10-8 cm-1.
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Affiliation(s)
- Krzysztof Pachucki
- Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland.
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35
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Nieto-Alvarez DA, Marín-León A, Luna-Rojero EE, Martínez-Magadan JM, Oviedo-Roa R, Pérez-Alvarez M, Dominguez-Zacarías G, Zamudio-Rivera LS. Nonquilibrium and Equilibrium Stationary States of Zwitterionic Surfactant Dynamic Adsorption on Limestone Cores at Oil-Reservoir Conditions. Ind Eng Chem Res 2018. [DOI: 10.1021/acs.iecr.7b03610] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- David A. Nieto-Alvarez
- Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas Norte 152, San Bartolo Atepehuacan, Ciudad de México 07730, México
| | - Adlaí Marín-León
- Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas Norte 152, San Bartolo Atepehuacan, Ciudad de México 07730, México
| | - Erick E. Luna-Rojero
- Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas Norte 152, San Bartolo Atepehuacan, Ciudad de México 07730, México
| | - José M. Martínez-Magadan
- Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas Norte 152, San Bartolo Atepehuacan, Ciudad de México 07730, México
| | - Raúl Oviedo-Roa
- Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas Norte 152, San Bartolo Atepehuacan, Ciudad de México 07730, México
| | - Marissa Pérez-Alvarez
- CONACyT Research Fellow- Instituto Mexicano del Petróleo, Gerencia Centro-Norte La Reforma Hidalgo, Carretera Pachuca a Ciudad Sahagún Km 7.5, Parque Industrial
Canacinta, Mineral de la Reforma, Hidalgo 42186, México
| | - Galileo Dominguez-Zacarías
- Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas Norte 152, San Bartolo Atepehuacan, Ciudad de México 07730, México
| | - Luis S. Zamudio-Rivera
- Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas Norte 152, San Bartolo Atepehuacan, Ciudad de México 07730, México
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Altmann RK, Dreissen LS, Salumbides EJ, Ubachs W, Eikema KSE. Deep-Ultraviolet Frequency Metrology of H_{2} for Tests of Molecular Quantum Theory. PHYSICAL REVIEW LETTERS 2018; 120:043204. [PMID: 29437464 DOI: 10.1103/physrevlett.120.043204] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Indexed: 06/08/2023]
Abstract
Molecular hydrogen and its isotopic and ionic species are benchmark systems for testing quantum chemical theory. Advances in molecular energy structure calculations enable the experimental verification of quantum electrodynamics and potentially a determination of the proton charge radius from H_{2} spectroscopy. We measure the ground state energy in ortho-H_{2} relative to the first electronically excited state by Ramsey-comb laser spectroscopy on the EF^{1}Σ_{g}^{+}-X^{1}Σ_{g}^{+}(0,0) Q1 transition. The resulting transition frequency of 2 971 234 992 965(73) kHz is 2 orders of magnitude more accurate than previous measurements. This paves the way for a considerably improved determination of the dissociation energy (D_{0}) for fundamental tests with molecular hydrogen.
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Affiliation(s)
- R K Altmann
- LaserLaB, Department of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - L S Dreissen
- LaserLaB, Department of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - E J Salumbides
- LaserLaB, Department of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - W Ubachs
- LaserLaB, Department of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - K S E Eikema
- LaserLaB, Department of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands
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Beyer A, Maisenbacher L, Matveev A, Pohl R, Khabarova K, Grinin A, Lamour T, Yost DC, Hänsch TW, Kolachevsky N, Udem T. The Rydberg constant and proton size from atomic hydrogen. Science 2017; 358:79-85. [DOI: 10.1126/science.aah6677] [Citation(s) in RCA: 225] [Impact Index Per Article: 32.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 08/28/2017] [Indexed: 11/03/2022]
Affiliation(s)
- Axel Beyer
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
| | | | - Arthur Matveev
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
| | - Randolf Pohl
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
| | - Ksenia Khabarova
- P.N. Lebedev Physical Institute, 119991 Moscow, Russia
- Russian Quantum Center, 143025 Skolkovo, Russia
| | - Alexey Grinin
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
| | - Tobias Lamour
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
| | - Dylan C. Yost
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
| | - Theodor W. Hänsch
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
- Ludwig-Maximilians-Universität, 80539 München, Germany
| | - Nikolai Kolachevsky
- P.N. Lebedev Physical Institute, 119991 Moscow, Russia
- Russian Quantum Center, 143025 Skolkovo, Russia
| | - Thomas Udem
- Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany
- Ludwig-Maximilians-Universität, 80539 München, Germany
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38
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Mata RA, Suhm MA. Benchmarking Quantum Chemical Methods: Are We Heading in the Right Direction? Angew Chem Int Ed Engl 2017; 56:11011-11018. [PMID: 28452424 PMCID: PMC5582598 DOI: 10.1002/anie.201611308] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 12/20/2016] [Indexed: 11/15/2022]
Abstract
Theoreticians and experimentalists should work together more closely to establish reliable rankings and benchmarks for quantum chemical methods. Comparison to carefully designed experimental benchmark data should be a priority. Guidelines to improve the situation for experiments and calculations are proposed.
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Affiliation(s)
- Ricardo A. Mata
- Institut für Physikalische ChemieUniversität GöttingenTammannstrasse 637077GöttingenGermany
| | - Martin A. Suhm
- Institut für Physikalische ChemieUniversität GöttingenTammannstrasse 637077GöttingenGermany
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39
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Mata RA, Suhm MA. Quantenchemische Methoden im Leistungsvergleich: Stimmt die Richtung noch? Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201611308] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Ricardo A. Mata
- Institut für Physikalische Chemie; Universität Göttingen; Tammannstraße 6 37077 Göttingen Deutschland
| | - Martin A. Suhm
- Institut für Physikalische Chemie; Universität Göttingen; Tammannstraße 6 37077 Göttingen Deutschland
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40
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Hill RJ. Review of experimental and theoretical status of the proton radius puzzle. EPJ WEB OF CONFERENCES 2017. [DOI: 10.1051/epjconf/201713701023] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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41
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Non-Born-Oppenheimer calculations of the rovibrational spectrum of H2 excited to the second rotational level. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2016.12.049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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42
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Puchalski M, Komasa J, Czachorowski P, Pachucki K. Complete α^{6} m Corrections to the Ground State of H_{2}. PHYSICAL REVIEW LETTERS 2016; 117:263002. [PMID: 28059550 DOI: 10.1103/physrevlett.117.263002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Indexed: 06/06/2023]
Abstract
We perform the calculation of all relativistic and quantum electrodynamic corrections of the order of α^{6} m to the ground electronic state of a hydrogen molecule and present improved results for the dissociation and the fundamental transition energies. These results open the window for the high-precision spectroscopy of H_{2} and related low-energy tests of fundamental interactions.
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Affiliation(s)
- Mariusz Puchalski
- Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznań, Poland
| | - Jacek Komasa
- Faculty of Chemistry, Adam Mickiewicz University, Umultowska 89b, 61-614 Poznań, Poland
| | - Paweł Czachorowski
- Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
| | - Krzysztof Pachucki
- Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
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43
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Trivikram TM, Niu ML, Wcisło P, Ubachs W, Salumbides EJ. Precision measurements and test of molecular theory in highly excited vibrational states of H 2 ( v = 11). APPLIED PHYSICS. B, LASERS AND OPTICS 2016; 122:294. [PMID: 32336882 PMCID: PMC7154793 DOI: 10.1007/s00340-016-6570-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 11/04/2016] [Indexed: 06/08/2023]
Abstract
Accurate E F 1 Σ g + - X 1 Σ g + transition energies in molecular hydrogen were determined for transitions originating from levels with highly excited vibrational quantum number, v = 11, in the ground electronic state. Doppler-free two-photon spectroscopy was applied on vibrationally excited H 2 ∗ , produced via the photodissociation of H2S, yielding transition frequencies with accuracies of 45 MHz or 0.0015 cm-1. An important improvement is the enhanced detection efficiency by resonant excitation to autoionizing 7 p π electronic Rydberg states, resulting in narrow transitions due to reduced ac-Stark effects. Using known EF level energies, the level energies of X(v = 11, J = 1, 3-5) states are derived with accuracies of typically 0.002 cm-1. These experimental values are in excellent agreement with and are more accurate than the results obtained from the most advanced ab initio molecular theory calculations including relativistic and QED contributions.
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Affiliation(s)
- T. Madhu Trivikram
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - M. L. Niu
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - P. Wcisło
- Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziądzka 5, 87-100 Toruń, Poland
| | - W. Ubachs
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - E. J. Salumbides
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
- Department of Physics, University of San Carlos, 6000 Cebu City, Philippines
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44
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Semeria L, Jansen P, Merkt F. Precision measurement of the rotational energy-level structure of the three-electron molecule He 2. J Chem Phys 2016; 145:204301. [PMID: 27908106 DOI: 10.1063/1.4967256] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The term values of all rotational levels of the 4He2+ X+ 2Σu+ (ν+=0) ground vibronic state with rotational quantum number N+ ≤ 19 have been determined with an accuracy of 8 × 10-4 cm-1 (∼25 MHz) by multichannel-quantum-defect-theory-assisted Rydberg spectroscopy of metastable He2∗. Comparison of these term values with term values recently calculated ab initio by Tung et al. [J. Chem. Phys. 136, 104309 (2012)] reveals discrepancies that rapidly increase with increasing rotational quantum number and reach values of 0.07 cm-1 (∼2.1 GHz) at N+ = 19.
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Affiliation(s)
- Luca Semeria
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Paul Jansen
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Frédéric Merkt
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
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45
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Artiukhin DG, Bieske EJ, Buchachenko AA. Ab Initio Characterization of the Electrostatic Complexes Formed by H2 Molecule and Cr(+), Mn(+), Cu(+), and Zn(+) Cations. J Phys Chem A 2016; 120:5006-15. [PMID: 26914616 DOI: 10.1021/acs.jpca.5b12700] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Equilibrium structures, dissociation energies, and rovibrational energy levels of the electrostatic complexes formed by molecular hydrogen and first-row S-state transition metal cations Cr(+), Mn(+), Cu(+), and Zn(+) are investigated ab initio. Extensive testing of the CCSD(T)-based approaches for equilibrium structures provides an optimal scheme for the potential energy surface calculations. These surfaces are calculated in two dimensions by keeping the H-H internuclear distance fixed at its equilibrium value in the complex. Subsequent variational calculations of the rovibrational energy levels permits direct comparison with data obtained from equilibrium thermochemical and spectroscopic measurements. Overall accuracy within 2-3% is achieved. Theoretical results are used to examine trends in hydrogen activation, vibrational anharmonicity, and rotational structure along the sequence of four electrostatic complexes covering the range from a relatively floppy van der Waals system (Mn(+)···H2) to an almost a rigid molecular ion (Cu(+)···H2).
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Affiliation(s)
- Denis G Artiukhin
- Department of Chemistry, Moscow State University , Moscow 119991, Russia
| | - Evan J Bieske
- School of Chemistry, The University of Melbourne , Parkville, VIC 3010, Australia
| | - Alexei A Buchachenko
- Skolkovo Institute of Science and Technology , 100 Novaya Street, Skolkovo, Odintsovsky District, Moscow Region 143025, Russia
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46
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Krechkivska O, Bacskay GB, Welsh BA, Nauta K, Kable SH, Stanton JF, Schmidt TW. The ionization energy of C2. J Chem Phys 2016; 144:144305. [DOI: 10.1063/1.4944932] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- O. Krechkivska
- School of Chemistry, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - G. B. Bacskay
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - B. A. Welsh
- School of Chemistry, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - K. Nauta
- School of Chemistry, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - S. H. Kable
- School of Chemistry, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - J. F. Stanton
- Department of Chemistry, The University of Texas at Austin, Austin, Texas 78712, USA
| | - T. W. Schmidt
- School of Chemistry, UNSW Sydney, Sydney, New South Wales 2052, Australia
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47
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Burgess DR. An Evaluation of Gas Phase Enthalpies of Formation for Hydrogen-Oxygen (H xO y) Species. JOURNAL OF RESEARCH OF THE NATIONAL INSTITUTE OF STANDARDS AND TECHNOLOGY 2016; 121:108-138. [PMID: 34434616 PMCID: PMC7339710 DOI: 10.6028/jres.121.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/11/2016] [Indexed: 06/13/2023]
Abstract
We have compiled gas phase enthalpies of formation for nine hydrogen-oxygen species (HxOy) and selected recommended values for H, O, OH, H2O, HO2, H2O2, O3, HO3, and H2O3. The compilation consists of values derived from experimental measurements, quantum chemical calculations, and prior evaluations. This work updates the recommended values in the NIST-JANAF (1985) and Gurvich et al. (1989) thermochemical tables for seven species. For two species, HO3 and H2O3 (important in atmospheric chemistry) and not found in prior thermochemical evaluations, we also provide supplementary data consisting of molecular geometries, vibrational frequencies, and torsional potentials which can be used to compute thermochemical functions. For all species, we also provide supplementary data consisting of zero point energies, vibrational frequencies, and ion reaction energetics.
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Affiliation(s)
- Donald R Burgess
- National Institute of Standards and Technology, Gaithersburg, MD 20899
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48
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Beyer M, Merkt F. Observation and Calculation of the Quasibound Rovibrational Levels of the Electronic Ground State of H2+. PHYSICAL REVIEW LETTERS 2016; 116:093001. [PMID: 26991172 DOI: 10.1103/physrevlett.116.093001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Indexed: 06/05/2023]
Abstract
Although the existence of quasibound rotational levels of the X^{+} ^{2}Σ_{g}^{+} ground state of H_{2}^{+} was predicted a long time ago, these states have never been observed. Calculated positions and widths of quasibound rotational levels located close to the top of the centrifugal barriers have not been reported either. Given the role that such states play in the recombination of H(1s) and H^{+} to form H_{2}^{+}, this lack of data may be regarded as one of the largest unknown aspects of this otherwise accurately known fundamental molecular cation. We present measurements of the positions and widths of the lowest-lying quasibound rotational levels of H_{2}^{+} and compare the experimental results with the positions and widths we calculate using a potential model for the X^{+} state of H_{2}^{+} which includes adiabatic, nonadiabatic, relativistic, and radiative corrections to the Born-Oppenheimer approximation.
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Affiliation(s)
- Maximilian Beyer
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - Frédéric Merkt
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
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49
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Hogan SD. Rydberg-Stark deceleration of atoms and molecules. EPJ TECHNIQUES AND INSTRUMENTATION 2016; 3:2. [PMID: 32355605 PMCID: PMC7175735 DOI: 10.1140/epjti/s40485-015-0028-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 12/27/2015] [Indexed: 06/06/2023]
Abstract
The large electric dipole moments associated with highly excited Rydberg states of atoms and molecules make gas-phase samples in these states very well suited to deceleration and trapping using inhomogeneous electric fields. The methods of Rydberg-Stark deceleration with which this can be achieved are reviewed here. Using these techniques, the longitudinal motion of beams of atoms and molecules moving at speeds as high as 2500 m/s have been manipulated, with changes in kinetic energy of up to |Δ E kin|=1.3×10-20 J (|Δ E kin|/e=80 meV or |Δ E kin|/h c=650 cm -1) achieved, while decelerated and trapped samples with number densities of 106- 107 cm -3 and translational temperatures of ∼150 mK have been prepared. Applications of these samples in areas of research at the interface between physics and physical chemistry are discussed.
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Affiliation(s)
- Stephen D. Hogan
- Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT UK
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50
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