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Schatz GC, Wodtke AM, Yang X. Spiers Memorial Lecture: New directions in molecular scattering. Faraday Discuss 2024; 251:9-62. [PMID: 38764350 DOI: 10.1039/d4fd00015c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/21/2024]
Abstract
The field of molecular scattering is reviewed as it pertains to gas-gas as well as gas-surface chemical reaction dynamics. We emphasize the importance of collaboration of experiment and theory, from which new directions of research are being pursued on increasingly complex problems. We review both experimental and theoretical advances that provide the modern toolbox available to molecular-scattering studies. We distinguish between two classes of work. The first involves simple systems and uses experiment to validate theory so that from the validated theory, one may learn far more than could ever be measured in the laboratory. The second class involves problems of great complexity that would be difficult or impossible to understand without a partnership of experiment and theory. Key topics covered in this review include crossed-beams reactive scattering and scattering at extremely low energies, where quantum effects dominate. They also include scattering from surfaces, reactive scattering and kinetics at surfaces, and scattering work done at liquid surfaces. The review closes with thoughts on future promising directions of research.
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Affiliation(s)
- George C Schatz
- Dept of Chemistry, Northwestern University, Evanston, Illinois 60208, USA
| | - Alec M Wodtke
- Institute for Physical Chemistry, Georg August University, Goettingen, Germany
- Max Planck Institute for Multidisciplinary Natural Sciences, Goettingen, Germany.
- International Center for the Advanced Studies of Energy Conversion, Georg August University, Goettingen, Germany
| | - Xueming Yang
- Dalian Institute for Chemical Physics, Chinese Academy of Sciences, Dalian, China
- Department of Chemistry, College of Science, Southern University of Science and Technology, Shenzhen, China
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2
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Zhang Y, Wang Q, Ni S, Ji L, Cao Z, Qi J. The effect of spin-orbit coupling on molecular properties: Potential energy curve, transition dipole moment and laser cooling scheme of NH. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 267:120578. [PMID: 34815177 DOI: 10.1016/j.saa.2021.120578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 10/08/2021] [Accepted: 10/31/2021] [Indexed: 06/13/2023]
Abstract
The influence of spin-orbit coupling on the cooling of NH molecular laser is investigated based on the ab initio theory. The potential energy curves (PECs) and spectral constants for four Λ-S states (X3Σ-, a1Δ, b1Σ+ and A3Π) and eight Ω states [Formula: see text] a1Δ2, [Formula: see text] and [Formula: see text] ) of NH molecule are obtained by the multi-reference configuration interaction (MRCI) plus Davidson correction. The spectroscopic constants (Re, ωe, ωeχe, Be, De) are obtained by solving the one dimensional radial Schrödinger equation, and the results are almost the same as the previously reported data. In addition, the transition dipole moment, permanent dipole moment, Franck-Condon factors, and radiative lifetime of NH molecule are also acquired. Also, the effects of the intermediate state on the [Formula: see text] , [Formula: see text] and [Formula: see text] transitions are considered. The feasible laser cooling schemes using a single laser are formulated. In the proposed cooling scheme, there wavelengths for the [Formula: see text] are used, the main pump lasers are λ00 = 335.74 nm. The feasible transition is based on this. It is found that spin-orbit coupling has a significant effect on potential energy curves, permanent dipole moments, transition dipole moments and vibration energy levels.
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Affiliation(s)
- Yunguang Zhang
- School of Science, Xi'an University of Posts and Telecommunications, Xi'an 710121, China.
| | - Qihao Wang
- School of Science, Xi'an University of Posts and Telecommunications, Xi'an 710121, China
| | - Simin Ni
- School of Science, Xi'an University of Posts and Telecommunications, Xi'an 710121, China
| | - Lingling Ji
- School of Science, Xi'an University of Posts and Telecommunications, Xi'an 710121, China
| | - Zhanli Cao
- School of Science, Xi'an University of Posts and Telecommunications, Xi'an 710121, China
| | - Jiangxia Qi
- School of Science, Xi'an University of Posts and Telecommunications, Xi'an 710121, China
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3
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Zirkelbach J, Mirzaei M, Deperasinska I, Kozankiewicz B, Gurlek B, Shkarin A, Utikal T, Götzinger S, Sandoghdar V. High-resolution vibronic spectroscopy of a single molecule embedded in a crystal. J Chem Phys 2022; 156:104301. [DOI: 10.1063/5.0081297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | | | | | - Boleslaw Kozankiewicz
- Radiation Physics and Spectroscopy, Institute of Physics Polish Academy of Sciences, Poland
| | - Burak Gurlek
- Sandoghdar Division, Max Planck Institute for the Science of Light, Germany
| | | | - Tobias Utikal
- Max Planck Institute for the Science of Light, Germany
| | | | - Vahid Sandoghdar
- Division Sandoghdar, Max Planck Institute for the Science of Light, Germany
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4
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Aggarwal P, Yin Y, Esajas K, Bethlem HL, Boeschoten A, Borschevsky A, Hoekstra S, Jungmann K, Marshall VR, Meijknecht TB, Mooij MC, Timmermans RGE, Touwen A, Ubachs W, Willmann L. Deceleration and Trapping of SrF Molecules. PHYSICAL REVIEW LETTERS 2021; 127:173201. [PMID: 34739281 DOI: 10.1103/physrevlett.127.173201] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2021] [Accepted: 09/07/2021] [Indexed: 06/13/2023]
Abstract
We report on the electrostatic trapping of neutral SrF molecules. The molecules are captured from a cryogenic buffer-gas beam source into the moving traps of a 4.5-m-long traveling-wave Stark decelerator. The SrF molecules in X^{2}Σ^{+}(v=0,N=1) state are brought to rest as the velocity of the moving traps is gradually reduced from 190 m/s to zero. The molecules are held for up to 50 ms in multiple electric traps of the decelerator. The trapped packets have a volume (FWHM) of 1 mm^{3} and a velocity spread of 5(1) m/s, which corresponds to a temperature of 60(20) mK. Our result demonstrates a factor 3 increase in the molecular mass that has been Stark decelerated and trapped. Heavy molecules (mass>100 amu) offer a highly increased sensitivity to probe physics beyond the standard model. This work significantly extends the species of neutral molecules of which slow beams can be created for collision studies, precision measurement, and trapping experiments.
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Affiliation(s)
- P Aggarwal
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - Y Yin
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - K Esajas
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - H L Bethlem
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Department of Physics and Astronomy, and LaserLaB, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - A Boeschoten
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - A Borschevsky
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - S Hoekstra
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - K Jungmann
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - V R Marshall
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - T B Meijknecht
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - M C Mooij
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
- Department of Physics and Astronomy, and LaserLaB, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - R G E Timmermans
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - A Touwen
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
| | - W Ubachs
- Department of Physics and Astronomy, and LaserLaB, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - L Willmann
- Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, Zernikelaan 25, 9747 AA Groningen, The Netherlands
- Nikhef, National Institute for Subatomic Physics, Science Park 105, 1098 XG Amsterdam, The Netherlands
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Maitre PA, Bieniek MS, Kechagiopoulos PN. Plasma-enhanced catalysis for the upgrading of methane: a review of modelling and simulation methods. REACT CHEM ENG 2020. [DOI: 10.1039/d0re00024h] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Modelling methods and simulation works on the upgrading of methane via plasma and plasma-enhanced catalysis reviewed.
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Affiliation(s)
- Pierre-André Maitre
- Chemical and Materials Engineering Group
- School of Engineering
- University of Aberdeen
- Aberdeen
- UK
| | - Matthew S. Bieniek
- Chemical and Materials Engineering Group
- School of Engineering
- University of Aberdeen
- Aberdeen
- UK
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6
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Cremers T, Chefdeville S, Bakker JM, Leo Meerts W, van de Meerakker SYT. Direct excitation of the spin-orbit forbidden X2π 3/2 ← X2π 1/2 transition in NO using the intra-cavity free electron laser FELICE. Mol Phys 2019. [DOI: 10.1080/00268976.2019.1589008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Theo Cremers
- Institute for Molecules and Materials, Radboud University, Nijmegen, Netherlands
| | - Simon Chefdeville
- Institute for Molecules and Materials, Radboud University, Nijmegen, Netherlands
| | - Joost M. Bakker
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Nijmegen, Netherlands
| | - W. Leo Meerts
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Nijmegen, Netherlands
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7
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Palmer JE, Hogan SD. Electric Rydberg-Atom Interferometry. PHYSICAL REVIEW LETTERS 2019; 122:250404. [PMID: 31347868 DOI: 10.1103/physrevlett.122.250404] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Indexed: 06/10/2023]
Abstract
An electric analogue of the longitudinal Stern-Gerlach matter-wave interferometer has been realized for atoms in Rydberg states with high principal quantum number n. The experiments were performed with He atoms prepared in coherent superpositions of the n=55 and n=56 circular Rydberg states in a zero electric field by a π/2 pulse of resonant microwave radiation. These atoms were subjected to a pulsed inhomogeneous electric field to generate a superposition of momentum states before a π pulse was applied to invert the internal states. The same pulsed inhomogeneous electric field was then reapplied for a second time to transform the motional states to have equal momenta before a further π/2 pulse was employed to interrogate the final Rydberg state populations. This Hahn-echo microwave pulse sequence, interspersed with a pair of equivalent inhomogeneous electric field pulses, yielded two spatially separated matter waves. Interferences between these matter waves were observed as oscillations in the final Rydberg state populations as the amplitude of the pulsed electric field gradients was adjusted.
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Affiliation(s)
- J E Palmer
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - S D Hogan
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
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8
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Gao Y, Wan M. Vibrational branching ratios and radiative lifetimes in the laser cooling of AlBr. Phys Chem Chem Phys 2018; 19:5519-5524. [PMID: 28165081 DOI: 10.1039/c6cp08181a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The feasibility of laser cooling of the AlBr molecule is investigated using ab initio quantum chemistry. Potential energy curves, permanent dipole moments, and transition dipole moments for the ground state X1Σ+ and the first two excited states (a3Π and A1Π) are calculated using the multi-reference configuration interaction plus Davidson corrections (MRCI+Q) method with the ACVQZ basis set; the spin-orbit coupling effects are also taken into account in electronic structure calculations at the MRCI level. Based on the acquired potential energy curves and transition dipole moments, highly diagonally distributed Franck-Condon factors (f00 = 0.9540, f11 = 0.8172) and vibrational branching ratios (R00 = 0.9708, R11 = 0.8420) for the transition are determined. Radiative lifetime calculations of the A1Π1 (ν' = 0-4) state are found to be short (9.16-11.48 ns) enough for rapid laser cooling. The proposed main cycling laser drives the transition at the wavelength λ00 = 279.19 nm. The vibrational branching loss ratios of the A1Π1 (ν') state to the intervening states a3Π0+ and a3Π1 are small (<5.2 × 10-6) enough to be negligible. The present theoretical results indicate that the AlBr molecule is a promising candidate for laser cooling.
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Affiliation(s)
- Yufeng Gao
- National Demonstration Center for Experimental Physics Education, College of Physics and Materials Science, Henan Normal University, Xinxiang 453007, China.
| | - Mingjie Wan
- Computational Physics Key Laboratory of Sichuan Province, Yibin University, Yibin 644007, China
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9
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Affiliation(s)
- Stefan Willitsch
- Department of Chemistry; University of Basel; Klingelbergstrasse 80, 4056 Basel Switzerland
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10
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Tain RW, Scotti AM, Li W, Zhou XJ, Cai K. Imaging short-lived reactive oxygen species (ROS) with endogenous contrast MRI. J Magn Reson Imaging 2017; 47:222-229. [PMID: 28503732 DOI: 10.1002/jmri.25763] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 04/26/2017] [Indexed: 12/12/2022] Open
Abstract
PURPOSE To characterize the relaxation properties of reactive oxygen species (ROS) for the development of endogenous ROS contrast magnetic resonance imaging (MRI). MATERIALS AND METHODS ROS-producing phantoms and animal models were imaged at 9.4T MRI to obtain T1 and T2 maps. Egg white samples treated with varied concentrations of hydrogen peroxide (H2 O2 ) were used to evaluate the effect of produced ROS in T1 and T2 for up to 4 hours. pH and temperature changes due to H2 O2 treatment in egg white were also monitored. The influences from H2 O2 itself and oxygen were evaluated in bovine serum albumin (BSA) solution producing no ROS. In addition, dynamic temporal changes of T1 in H2 O2 -treated egg white samples were used to estimate ROS concentration over time and hence the detection sensitivity of relaxation-based endogenous ROS MRI. The relaxivity of ROS was compared with that of Gd-DTPA as a reference. Finally, the feasibility of in vivo ROS MRI with T1 mapping acquired using an inversion recovery sequence was demonstrated with a well-established rotenone-treated mouse model (n = 6). RESULTS pH and temperature changes in treated egg white samples were insignificant (<0.1 unit and <1°C, respectively). T1 relaxation time in the H2 O2 -treated egg white was reduced significantly (P < 0.05), while there was only small reduction in T2 (<10%). In the H2 O2 -treated BSA solution that produce no ROS, there was a small change in T1 due to H2 O2 itself (±1%), although a significant T2 -shortening effect was observed (>10%, P < 0.05). Also, there was a small reduction in T1 (13 ± 1%) and T2 (1 ± 2%) from molecular oxygen. The detection sensitivity of ROS MRI was estimated around 10 pM. The T1 relaxivity of ROS was found to be much higher than that of Gd-DTPA (3.4 × 107 vs. 0.9 s-1 ·mM-1 ). Finally, significantly reduced T1 was observed in rotenone-treated mouse brain (5.1 ± 2.5%, P < 0.05). CONCLUSION We demonstrated in the study that endogenous ROS MRI based on the paramagnetic effect has sensitivity for in vitro and in vivo applications. LEVEL OF EVIDENCE 2 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2018;47:222-229.
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Affiliation(s)
- Rong-Wen Tain
- Department of Radiology, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA.,Center for MR Research, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Alessandro M Scotti
- Department of Radiology, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA.,Center for MR Research, University of Illinois at Chicago, Chicago, Illinois, USA.,Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Weiguo Li
- Research Resource Center, University of Illinois at Chicago, Chicago, Illinois, USA.,Department of Radiology, Feinberg School of Medicine, Northwestern University, Evanston, Illinois, USA
| | - Xiaohong Joe Zhou
- Department of Radiology, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA.,Center for MR Research, University of Illinois at Chicago, Chicago, Illinois, USA.,Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois, USA
| | - Kejia Cai
- Department of Radiology, College of Medicine, University of Illinois at Chicago, Chicago, Illinois, USA.,Center for MR Research, University of Illinois at Chicago, Chicago, Illinois, USA.,Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois, USA
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11
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A novel molecular synchrotron for cold collision and EDM experiments. Sci Rep 2016; 6:32663. [PMID: 27600539 PMCID: PMC5013392 DOI: 10.1038/srep32663] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 08/11/2016] [Indexed: 11/09/2022] Open
Abstract
Limited by the construction demands, the state-of-the-art molecular synchrotrons consist of only 40 segments that hardly make a good circle. Imperfections in the circular structure will lead to the appearance of unstable velocity regions (i.e. stopbands), where molecules of certain forward velocity will be lost from the structure. In this paper, we propose a stopband-free molecular synchrotron. It contains 1570 ring electrodes, which nearly make a perfect circle, capable of confining both light and heavy polar molecules in the low-field-seeking states. Molecular packets can be conveniently manipulated with this synchrotron by various means, like acceleration, deceleration or even trapping. Trajectory calculations are carried out using a pulsed 88SrF molecular beam with a forward velocity of 50 m/s. The results show that the molecular beam can make more than 500 round trips inside the synchrotron with a 1/e lifetime of 6.2 s. The synchrotron can find potential applications in low-energy collision and reaction experiments or in the field of precision measurements, such as the searches for electric dipole moment of elementary particles.
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12
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Ploenes L, Haas D, Zhang D, van de Meerakker SYT, Willitsch S. Cold and intense OH radical beam sources. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:053305. [PMID: 27250412 DOI: 10.1063/1.4948917] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We present the design and performance of two supersonic radical beam sources: a conventional pinhole-discharge source and a dielectric barrier discharge (DBD) source, both based on the Nijmegen pulsed valve. Both designs have been characterized by discharging water molecules seeded in the rare gases Ar, Kr, or Xe. The resulting OH radicals have been detected by laser-induced fluorescence. The measured OH densities are (3.0 ± 0.6) × 10(11) cm(-3) and (1.0 ± 0.5) × 10(11) cm(-3) for the pinhole-discharge and DBD sources, respectively. The beam profiles for both radical sources show a relative longitudinal velocity spread of about 10%. The absolute rotational ground state population of the OH beam generated from the pinhole-discharge source has been determined to be more than 98%. The DBD source even produces a rotationally colder OH beam with a population of the ground state exceeding 99%. For the DBD source, addition of O2 molecules to the gas mixture increases the OH beam density by a factor of about 2.5, improves the DBD valve stability, and allows to tune the mean velocity of the radical beam.
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Affiliation(s)
- Ludger Ploenes
- Institute for Molecules and Materials, Radboud University, Heijendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Dominik Haas
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Dongdong Zhang
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | | | - Stefan Willitsch
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
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13
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Eberle P, Dörfler AD, von Planta C, Ravi K, Haas D, Zhang D, van de Meerakker SYT, Willitsch S. Ion-Atom and Ion-Molecule Hybrid Systems: Ion-Neutral Chemistry at Ultralow Energies. ACTA ACUST UNITED AC 2015. [DOI: 10.1088/1742-6596/635/1/012012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Chang YP, Horke DA, Trippel S, Küpper J. Spatially-controlled complex molecules and their applications. INT REV PHYS CHEM 2015. [DOI: 10.1080/0144235x.2015.1077838] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Yuan-Pin Chang
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Daniel A. Horke
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Sebastian Trippel
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany
| | - Jochen Küpper
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, 22607 Hamburg, Germany
- Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
- The Hamburg Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
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15
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Abstract
Over the past decade, and particularly the past five years, a quiet revolution has been building at the border between atomic physics and experimental quantum chemistry. The rapid development of techniques for producing cold and even ultracold molecules without a perturbing rare-gas cluster shell is now enabling the study of chemical reactions and scattering at the quantum scattering limit with only a few partial waves contributing to the incident channel. Moreover, the ability to perform these experiments with nonthermal distributions comprising one or a few specific states enables the observation and even full control of state-to-state collision rates in this computation-friendly regime: This is perhaps the most elementary study possible of scattering and reaction dynamics.
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Affiliation(s)
- Benjamin K Stuhl
- Joint Quantum Institute, National Institute of Standards and Technology and University of Maryland, Gaithersburg, Maryland 20899
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16
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Altinay G, Macdonald RG. Determination of the Rate Constant for the OH(X2Π) + OH(X2Π) → H2O + O(3P) Reaction Over the Temperature Range 295 to 701 K. J Phys Chem A 2013; 118:38-54. [DOI: 10.1021/jp409344q] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gokhan Altinay
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439-4381, United States
| | - R. Glen Macdonald
- Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439-4381, United States
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17
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Affiliation(s)
- Mikhail Lemeshko
- a ITAMP, Harvard-Smithsonian Center for Astrophysics , Cambridge , MA , 02138 , USA
- b Physics Department , Harvard University , Cambridge , MA , 02138 , USA
- c Kavli Institute for Theoretical Physics , University of California , Santa Barbara , CA , 93106 , USA
| | - Roman V. Krems
- c Kavli Institute for Theoretical Physics , University of California , Santa Barbara , CA , 93106 , USA
- d Department of Chemistry , University of British Columbia , BC V6T 1Z1, Vancouver , Canada
| | - John M. Doyle
- b Physics Department , Harvard University , Cambridge , MA , 02138 , USA
| | - Sabre Kais
- e Departments of Chemistry and Physics , Purdue University , West Lafayette , IN , 47907 , USA
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18
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Versolato OO, Schwarz M, Hansen AK, Gingell AD, Windberger A, Kłosowski L, Ullrich J, Jensen F, Crespo López-Urrutia JR, Drewsen M. Decay rate measurement of the first vibrationally excited state of MgH+ in a cryogenic Paul trap. PHYSICAL REVIEW LETTERS 2013; 111:053002. [PMID: 23952392 DOI: 10.1103/physrevlett.111.053002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Indexed: 06/02/2023]
Abstract
We present a method to measure the decay rate of the first excited vibrational state of polar molecular ions that are part of a Coulomb crystal in a cryogenic linear Paul trap. Specifically, we have monitored the decay of the |ν = 1, J = 1)(X) towards the |ν = 0, J = 0)(X) level in MgH+ by saturated laser excitation of the |ν = 0, J = 2)(X)-|ν = 1, J = 1)(X) transition followed by state selective resonance enhanced two-photon dissociation out of the |ν = 0, J=2)(X) level. The experimentally observed rate of 6.32(0.69) s(-1) is in excellent agreement with the theory value of 6.13(0.03) s(-1) (this Letter). The technique enables the determination of decay rates, and thus absorption strengths, with an accuracy at the few percent level.
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Affiliation(s)
- O O Versolato
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany.
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19
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20
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Rate coefficient for the important interstellar radiative association between and H2 from classical reaction dynamics. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2012.10.057] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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21
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Hutzler NR, Lu HI, Doyle JM. The Buffer Gas Beam: An Intense, Cold, and Slow Source for Atoms and Molecules. Chem Rev 2012; 112:4803-27. [PMID: 22571401 DOI: 10.1021/cr200362u] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Nicholas R. Hutzler
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts
02138, United States
| | - Hsin-I Lu
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts
02138, United States
| | - John M. Doyle
- Department of Physics, Harvard University, 17 Oxford Street, Cambridge, Massachusetts
02138, United States
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22
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van de Meerakker SYT, Bethlem HL, Vanhaecke N, Meijer G. Manipulation and Control of Molecular Beams. Chem Rev 2012; 112:4828-78. [DOI: 10.1021/cr200349r] [Citation(s) in RCA: 247] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Hendrick L. Bethlem
- Institute for Lasers, Life and
Biophotonics, VU University Amsterdam,
De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Nicolas Vanhaecke
- Laboratoire Aimé Cotton, CNRS, Bâtiment 505, Université Paris-Sud,
91405 Orsay, France
| | - Gerard Meijer
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin,
Germany
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23
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Janssen LMC, Żuchowski PS, van der Avoird A, Hutson JM, Groenenboom GC. Cold and ultracold NH–NH collisions: The field-free case. J Chem Phys 2011; 134:124309. [DOI: 10.1063/1.3570596] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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25
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Wall TE, Kanem JF, Dyne JM, Hudson JJ, Sauer BE, Hinds EA, Tarbutt MR. Stark deceleration of CaF molecules in strong- and weak-field seeking states. Phys Chem Chem Phys 2011; 13:18991-9. [DOI: 10.1039/c1cp21254k] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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26
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Hogan SD, Motsch M, Merkt F. Deceleration of supersonic beams using inhomogeneous electric and magnetic fields. Phys Chem Chem Phys 2011; 13:18705-23. [DOI: 10.1039/c1cp21733j] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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Juanes-Marcos JC, Quéméner G, Kendrick BK, Balakrishnan N. Ultracold collisions and reactions of vibrationally excited OH radicals with oxygen atoms. Phys Chem Chem Phys 2011; 13:19067-76. [DOI: 10.1039/c1cp21141b] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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28
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Janssen LMC, Groenenboom GC, van der Avoird A, Żuchowski PS, Podeszwa R. Ab initio potential energy surfaces for NH(Σ3−)–NH(Σ3−) with analytical long range. J Chem Phys 2009; 131:224314. [DOI: 10.1063/1.3268920] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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29
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Pavlovic Z, Tscherbul TV, Sadeghpour HR, Groenenboom GC, Dalgarno A. Cold Collisions of OH(2Π) Molecules with He Atoms in External Fields. J Phys Chem A 2009; 113:14670-80. [DOI: 10.1021/jp904512r] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Z. Pavlovic
- ITAMP, Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, Department of Physics, University of Connecticut, Storrs, Connecticut 06269, Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, and Theoretical Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - T. V. Tscherbul
- ITAMP, Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, Department of Physics, University of Connecticut, Storrs, Connecticut 06269, Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, and Theoretical Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - H. R. Sadeghpour
- ITAMP, Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, Department of Physics, University of Connecticut, Storrs, Connecticut 06269, Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, and Theoretical Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - G. C. Groenenboom
- ITAMP, Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, Department of Physics, University of Connecticut, Storrs, Connecticut 06269, Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, and Theoretical Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - A. Dalgarno
- ITAMP, Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, Department of Physics, University of Connecticut, Storrs, Connecticut 06269, Harvard-MIT Center for Ultracold Atoms, Cambridge, Massachusetts 02138, and Theoretical Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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30
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Schnell M, Meijer G. Cold Molecules: Preparation, Applications, and Challenges. Angew Chem Int Ed Engl 2009; 48:6010-31. [DOI: 10.1002/anie.200805503] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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31
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Schnell M, Meijer G. Kalte Moleküle: Herstellung, Anwendungen und Herausforderungen. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200805503] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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32
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Affiliation(s)
- Samuel A. Meek
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
| | - Horst Conrad
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
| | - Gerard Meijer
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
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33
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Affiliation(s)
- Ramin M. Abolfath
- Department of Radiation Oncology, University of Texas Southwestern Medical Center, Dallas, Texas 75390
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34
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35
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Tscherbul TV, Groenenboom GC, Krems RV, Dalgarno A. Dynamics of OH(2Π)–He collisions in combined electric and magnetic fields. Faraday Discuss 2009; 142:127-41; discussion 221-55. [DOI: 10.1039/b819198k] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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37
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van der Loo MPJ, Groenenboom GC. Erratum: "Theoretical transition probabilities for the OH Meinel system" [J. Chem. Phys. 126, 114314 (2007)]. J Chem Phys 2008; 128:159902. [PMID: 18433289 DOI: 10.1063/1.2899016] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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38
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Campbell WC, Groenenboom GC, Lu HI, Tsikata E, Doyle JM. Time-domain measurement of spontaneous vibrational decay of magnetically trapped NH. PHYSICAL REVIEW LETTERS 2008; 100:083003. [PMID: 18352622 DOI: 10.1103/physrevlett.100.083003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Indexed: 05/26/2023]
Abstract
The v=1-->0 radiative lifetime of NH(X(3)Sigma(-),v=1,N=0) is determined to be tau_(rad,exp.)=37.0+/-0.5_(stat)+2.0/-0.8_(syst) ms, corresponding to a transition dipole moment of |mu_(10)|=0.0540_(-0.0018)(+0.0009) D. To achieve sufficiently long observation times, NH(X;{3}Sigma;{-},v=1) radicals are magnetically trapped using helium buffer-gas loading. The rate constant for background helium-induced collisional quenching was determined to be k_(v=1)<3.9x10(-15) cm(3) s(-1), which yields the quoted systematic uncertainty on tau_{rad,exp.}. With a new ab initio dipole moment function and a Rydberg-Klein-Rees potential, we calculate a lifetime of 36.99 ms, in agreement with our experimental value.
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Affiliation(s)
- Wesley C Campbell
- Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
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Gilijamse JJ, Hoekstra S, Meek SA, Metsälä M, van de Meerakker SYT, Meijer G, Groenenboom GC. The radiative lifetime of metastable CO (aΠ3, v=0). J Chem Phys 2007; 127:221102. [DOI: 10.1063/1.2813888] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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41
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van der Loo MPJ, Groenenboom GC. Theoretical transition probabilities for the OH Meinel system. J Chem Phys 2007; 126:114314. [PMID: 17381213 DOI: 10.1063/1.2646859] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The authors present a new potential energy curve, electric dipole moment function, and spin-orbit coupling function for OH in the X 2Pi state, based on high-level ab initio calculations. These properties, combined with a spectroscopically parametrized lambda-type doubling Hamiltonian, are used to compute the Einstein A coefficients and photoabsorption cross sections for the OH Meinel transitions. The authors investigate the effect of spin-orbit coupling on the lifetimes of rovibrationally excited states. Comparing their results with earlier ab initio calculations, they conclude that their dipole moment and potential energy curve give the best agreement with experimental data to date. The results are made available via EPAPS Document No. E-JCPSAG-017709.
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Affiliation(s)
- Mark P J van der Loo
- Theoretical Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Toernooiveld 1, 6525ED Nijmegen, The Netherlands
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42
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Tscherbul TV, Krems RV. Manipulating spin-dependent interactions in rotationally excited cold molecules with electric fields. J Chem Phys 2006; 125:194311. [PMID: 17129107 DOI: 10.1063/1.2374896] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We use rigorous quantum mechanical theory to study collisions of magnetically oriented cold molecules in the presence of superimposed electric and magnetic fields. It is shown that electric fields suppress the spin-rotation interaction in rotationally excited 2Sigma molecules and inhibit rotationally elastic and inelastic transitions accompanied by electron spin reorientation. We demonstrate that electric fields enhance collisional spin relaxation in 3Sigma molecules and discuss the mechanisms for electric field control of spin-changing transitions in collisions of rotationally excited CaD(2Sigma) and ND(3Sigma) molecules with helium atoms. The propensities for spin depolarization in the rotationally excited molecules are analyzed based on the calculations of collision rate constants at T=0.5 K.
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Affiliation(s)
- T V Tscherbul
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada.
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43
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Weck PF, Balakrishnan N. Importance of long-range interactions in chemical reactions at cold and ultracold temperatures. INT REV PHYS CHEM 2006. [DOI: 10.1080/01442350600791894] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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44
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Abstract
▪ Abstract The motion of polar molecules can be controlled by time-varying inhomogeneous electric fields. In a Stark decelerator, this is exploited to accelerate, transport, or decelerate a fraction of a molecular beam. When combined with a trap, the decelerator provides a means to store the molecules for times up to seconds. Here, we review our efforts to produce cold molecules via this technique. In particular, we present a new generation Stark decelerator and electrostatic trap that selects a significant part of a molecular beam pulse that can be loaded into the trap. Deceleration and trapping experiments using a beam of OH radicals are discussed.
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45
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Staanum P, Kraft SD, Lange J, Wester R, Weidemüller M. Experimental investigation of ultracold atom-molecule collisions. PHYSICAL REVIEW LETTERS 2006; 96:023201. [PMID: 16486570 DOI: 10.1103/physrevlett.96.023201] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2005] [Indexed: 05/06/2023]
Abstract
Ultracold collisions between Cs atoms and Cs2 dimers in the electronic ground state are observed in an optically trapped gas of atoms and molecules. The Cs2 molecules are formed in the triplet ground state by cw photoassociation through the outer well of the 0-(g) (P3/2) excited electronic state. Inelastic atom-molecule collisions converting internal excitation into kinetic energy lead to a loss of Cs2 molecules from the dipole trap. Rate coefficients are determined for collisions involving Cs atoms in either the F=3 or F=4 hyperfine ground state, and Cs2 molecules in either highly vibrationally excited states (nu'=32-47) or in low vibrational states (nu'=4-6) of the a3 summation(u)+ triplet ground state. The rate coefficients beta approximately 10(-10) cm3/s are found to be largely independent of the vibrational and rotational excitation indicating unitary limited cross sections.
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Affiliation(s)
- Peter Staanum
- Physikalisches Institut, Universität Freiburg, Hermann-Herder-Strassee 3, 79104 Freiburg, Germany
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46
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Abstract
The merging of molecular beam methods with those of accelerator physics has yielded new tools to manipulate the motion of molecules. Over the last few years, decelerators, lenses, bunchers, traps, and storage rings for neutral molecules have been demonstrated. Molecular beams with a tunable velocity and with a tunable width of the velocity distribution can now be produced, and are expected to become a valuable tool in a variety of physical chemistry and chemical physics experiments. Here we present a compact molecular beam machine, capable of producing 3D spatially focused packets of state-selected accelerated or decelerated molecules.
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Affiliation(s)
- Cynthia E Heiner
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195, Berlin, Germany
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