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Zhao H, Sun Z. An improved method for reactive scatterings in ultra-cold conditions using the time-dependent approach. Phys Chem Chem Phys 2024; 26:22790-22797. [PMID: 39163005 DOI: 10.1039/d4cp02340d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/21/2024]
Abstract
A new efficient method for considering the long-range effect of reactive scattering processes in ultra-cold conditions has been developed using the time-dependent quantum wave packet theory, where the initial wave packet could be placed at a position near the interaction region. This is in contrast to previous methods, where the initial wave packet has to be placed far from the interaction region. The new method reduces the numerical effort significantly. Typical reactions, such as S(1D) + H2, D+ + H2, and 7Li + 7Li2 (v0 = 1, j0 = 0), under cold or ultra-cold conditions, are used to demonstrate the numerical efficiency of the new method.
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Affiliation(s)
- Hailin Zhao
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China.
| | - Zhigang Sun
- Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China.
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2
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Morita M, Kendrick BK, Kłos J, Kotochigova S, Brumer P, Tscherbul TV. Signatures of Non-universal Quantum Dynamics of Ultracold Chemical Reactions of Polar Alkali Dimer Molecules with Alkali Metal Atoms: Li( 2S) + NaLi( a3Σ +) → Na( 2S) + Li 2( a3Σ u+). J Phys Chem Lett 2023; 14:3413-3421. [PMID: 37001115 DOI: 10.1021/acs.jpclett.3c00159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Ultracold chemical reactions of weakly bound triplet-state alkali metal dimer molecules have recently attracted much experimental interest. We perform rigorous quantum scattering calculations with a new ab initio potential energy surface to explore the chemical reaction of spin-polarized NaLi(a3Σ+) and Li(2S) to form Li2(a3Σu+) and Na(2S). The reaction is exothermic and proceeds readily at ultralow temperatures. Significantly, we observe strong sensitivity of the total reaction rate to small variations of the three-body part of the Li2Na interaction at short range, which we attribute to a relatively small number of open Li2(a3Σu+) product channels populated in the reaction. This provides the first signature of highly non-universal dynamics seen in rigorous quantum reactive scattering calculations of an ultracold exothermic insertion reaction involving a polar alkali dimer molecule, opening up the possibility of probing microscopic interactions in atom+molecule collision complexes via ultracold reactive scattering experiments.
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Affiliation(s)
- Masato Morita
- Chemical Physics Theory Group, Department of Chemistry, and Center for Quantum Information and Quantum Control, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Brian K Kendrick
- Theoretical Division (T-1, MS B221), Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Jacek Kłos
- Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, United States
- Department of Physics, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Svetlana Kotochigova
- Department of Physics, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Paul Brumer
- Chemical Physics Theory Group, Department of Chemistry, and Center for Quantum Information and Quantum Control, University of Toronto, Toronto, Ontario M5S 3H6, Canada
| | - Timur V Tscherbul
- Department of Physics, University of Nevada, Reno, Nevada 89557, United States
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3
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Morita M, Krems RV, Tscherbul TV. Universal Probability Distributions of Scattering Observables in Ultracold Molecular Collisions. PHYSICAL REVIEW LETTERS 2019; 123:013401. [PMID: 31386401 DOI: 10.1103/physrevlett.123.013401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 05/09/2019] [Indexed: 06/10/2023]
Abstract
Currently, quantum dynamics theory cannot be used for quantitative predictions of molecular scattering observables at low temperatures because of two problems. The first problem is the extreme sensitivity of the low-temperature observables to details of potential energy surfaces (PESs) parametrizing the nuclear Schrödinger equation. The second problem is the large size of the basis sets required for the numerical integration of the Schrödinger equation for strongly interacting molecules in the presence of fields, which precludes the application of rigorous quantum theory to all but a few atom-molecule systems. Here, we show that, if the scattering problem is formulated as a probabilistic prediction, quantum theory can provide reliable results with exponentially reduced numerical effort. Specifically, we show that the probability distributions that an observable is in a certain range of values can be obtained by averaging the results of scattering calculations with much smaller basis sets than required for calculations of individual scattering cross sections. Moreover, we show that such distributions do not rely on the precise knowledge of the PES. This opens the possibility of making probabilistic predictions of experimentally relevant observables for a wide variety of molecular systems, currently considered out of reach of quantum dynamics theory. We demonstrate the approach by computing the probability for elastic scattering of CaH and SrOH molecules by Li atoms and SrF molecules by Rb atoms.
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Affiliation(s)
- Masato Morita
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - Roman V Krems
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
| | - Timur V Tscherbul
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
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4
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Yang D, Hu X, Zhang DH, Xie D. An improved coupled-states approximation including the nearest neighbor Coriolis couplings for diatom-diatom inelastic collision. J Chem Phys 2018; 148:084101. [PMID: 29495786 DOI: 10.1063/1.5010807] [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
Solving the time-independent close coupling equations of a diatom-diatom inelastic collision system by using the rigorous close-coupling approach is numerically difficult because of its expensive matrix manipulation. The coupled-states approximation decouples the centrifugal matrix by neglecting the important Coriolis couplings completely. In this work, a new approximation method based on the coupled-states approximation is presented and applied to time-independent quantum dynamic calculations. This approach only considers the most important Coriolis coupling with the nearest neighbors and ignores weaker Coriolis couplings with farther K channels. As a result, it reduces the computational costs without a significant loss of accuracy. Numerical tests for para-H2+ortho-H2 and para-H2+HD inelastic collision were carried out and the results showed that the improved method dramatically reduces the errors due to the neglect of the Coriolis couplings in the coupled-states approximation. This strategy should be useful in quantum dynamics of other systems.
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Affiliation(s)
- Dongzheng Yang
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Xixi Hu
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Dong H Zhang
- State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Daiqian Xie
- Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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5
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Jachymski K, Hapka M, Jankunas J, Osterwalder A. Experimental and Theoretical Studies of Low‐Energy Penning Ionization of NH
3
, CH
3
F, and CHF
3. Chemphyschem 2016; 17:3776-3782. [DOI: 10.1002/cphc.201600608] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 08/02/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Krzysztof Jachymski
- Faculty of Physics University of Warsaw Pasteura 5 02-093 Warsaw Poland
- Institute for Theoretical Physics III and Center for Integrated Quantum Science and Technology University of Stuttgart Pfaffenwaldring 57 70550 Stuttgart Germany
| | - Michał Hapka
- Faculty of Chemistry University of Warsaw Pasteura 1 02-093 Warsaw Poland
| | - Justin Jankunas
- Institute for Chemical Sciences and Engineering Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
- Deceased
| | - Andreas Osterwalder
- Institute for Chemical Sciences and Engineering Ecole Polytechnique Fédérale de Lausanne (EPFL) 1015 Lausanne Switzerland
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6
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Jankunas J, Jachymski K, Hapka M, Osterwalder A. Communication: Importance of rotationally inelastic processes in low-energy Penning ionization of CHF3. J Chem Phys 2016; 144:221102. [DOI: 10.1063/1.4953908] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Justin Jankunas
- Institute for Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Krzysztof Jachymski
- Faculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland
- Institute for Theoretical Physics III and Center for Integrated Quantum Science and Technology, University of Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany
| | - Michał Hapka
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
| | - Andreas Osterwalder
- Institute for Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
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8
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9
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Ulmanis J, Deiglmayr J, Repp M, Wester R, Weidemüller M. Ultracold Molecules Formed by Photoassociation: Heteronuclear Dimers, Inelastic Collisions, and Interactions with Ultrashort Laser Pulses. Chem Rev 2012; 112:4890-927. [PMID: 22931226 DOI: 10.1021/cr300215h] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Juris Ulmanis
- Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Philosophenweg
12, 69120 Heidelberg, Germany
| | - Johannes Deiglmayr
- Laboratorium für Physikalische
Chemie, ETH Zürich, Wolfgang-Pauli-Strasse
10, 8093 Zürich, Switzerland
| | - Marc Repp
- Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Philosophenweg
12, 69120 Heidelberg, Germany
| | - Roland Wester
- Institut für Ionenphysik
und Angewandte Physik, Universität Innsbruck, Technikerstrasse 25/3, 6020 Innsbruck, Austria
| | - Matthias Weidemüller
- Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Philosophenweg
12, 69120 Heidelberg, Germany
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10
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Affiliation(s)
- Goulven Quéméner
- JILA, University of Colorado,
Boulder, CO 80309-0440, United States
| | - Paul S. Julienne
- Joint Quantum Institute, NIST
and the University of Maryland, Gaithersburg, Maryland 20899-8423,
United States
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11
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Singh V, Hardman KS, Tariq N, Lu MJ, Ellis A, Morrison MJ, Weinstein JD. Chemical reactions of atomic lithium and molecular calcium monohydride at 1 K. PHYSICAL REVIEW LETTERS 2012; 108:203201. [PMID: 23003146 DOI: 10.1103/physrevlett.108.203201] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Indexed: 06/01/2023]
Abstract
Using cryogenic helium buffer-gas cooling, we have prepared dense samples of atomic lithium and molecular calcium monohydride at temperatures as low as 1 K. We have measured the Li+CaH→LiH+Ca chemical reaction, observed in both the accelerated disappearance of CaH in the presence of high densities of lithium and in the appearance of the LiH molecule.
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Affiliation(s)
- Vijay Singh
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
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12
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Bargueño P, Miret-Artés S, Gonzalo I. Quantum stochastic resonance in parity violating chiral molecules. Phys Chem Chem Phys 2011; 13:850-3. [PMID: 21063621 DOI: 10.1039/c0cp01319f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In order to explore parity violating effects in chiral molecules, of interest in some models of evolution towards homochirality, quantum stochastic resonance (QSR) is studied for the population difference between the two enantiomers of a chiral molecule (hence for the optical activity of the sample), under low viscous friction and in the deep quantum regime. The molecule is described by a two-state model in an asymmetric double well potential where the asymmetry is given by the known predicted parity violating energy difference (PVED) between enantiomers. In the linear response to an external driving field that lowers and rises alternatively each one of the minima of the well, a signal of QSR is predicted only in the case that the PVED is different from zero, the resonance condition being independent on tunneling between the two enantiomers. It is shown that, at resonance, the fluctuations of the first order contribution to the internal energy are zero. Due to the small value of the PVED, the resonance would occur in the ultracold regime. Some proposals concerning the external driving field are suggested.
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Affiliation(s)
- Pedro Bargueño
- Instituto de Física Fundamental (CSIC), Serrano 123, 28006 Madrid, Spain.
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13
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Julienne PS, Hanna TM, Idziaszek Z. Universal ultracold collision rates for polar molecules of two alkali-metal atoms. Phys Chem Chem Phys 2011; 13:19114-24. [DOI: 10.1039/c1cp21270b] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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14
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Bargueño P, de Tudela RP, Miret-Artés S, Gonzalo I. An alternative route to detect parity violating energy differences through Bose–Einstein condensation of chiral molecules. Phys Chem Chem Phys 2011; 13:806-10. [DOI: 10.1039/c0cp00907e] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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15
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Simbotin I, Ghosal S, Côté R. A case study in ultracold reactive scattering: D + H2. Phys Chem Chem Phys 2011; 13:19148-55. [PMID: 21976145 DOI: 10.1039/c1cp21982k] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Ion Simbotin
- University of Connecticut, Department of Physics, 2152 Hillside Road, U-3046, Storrs, CT 06269, USA.
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16
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Soldán P. Potential energy surface for spin-polarized rubidium trimer. J Chem Phys 2010; 132:234308. [DOI: 10.1063/1.3455710] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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17
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Lipoff SH, Herschbach DR. Low-energy limit for tunnelling subject to an Eckart potential barrier. Mol Phys 2010. [DOI: 10.1080/00268971003662912] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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18
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Chandler DW. Cold and ultracold molecules: Spotlight on orbiting resonances. J Chem Phys 2010; 132:110901. [DOI: 10.1063/1.3357286] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Ospelkaus S, Ni KK, Wang D, de Miranda MHG, Neyenhuis B, Quéméner G, Julienne PS, Bohn JL, Jin DS, Ye J. Quantum-state controlled chemical reactions of ultracold potassium-rubidium molecules. Science 2010; 327:853-7. [PMID: 20150499 DOI: 10.1126/science.1184121] [Citation(s) in RCA: 319] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
How does a chemical reaction proceed at ultralow temperatures? Can simple quantum mechanical rules such as quantum statistics, single partial-wave scattering, and quantum threshold laws provide a clear understanding of the molecular reactivity under a vanishing collision energy? Starting with an optically trapped near-quantum-degenerate gas of polar 40K87Rb molecules prepared in their absolute ground state, we report experimental evidence for exothermic atom-exchange chemical reactions. When these fermionic molecules were prepared in a single quantum state at a temperature of a few hundred nanokelvin, we observed p-wave-dominated quantum threshold collisions arising from tunneling through an angular momentum barrier followed by a short-range chemical reaction with a probability near unity. When these molecules were prepared in two different internal states or when molecules and atoms were brought together, the reaction rates were enhanced by a factor of 10 to 100 as a result of s-wave scattering, which does not have a centrifugal barrier. The measured rates agree with predicted universal loss rates related to the two-body van der Waals length.
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Affiliation(s)
- S Ospelkaus
- JILA, NIST and University of Colorado, Department of Physics, University of Colorado, Boulder, CO 80309, USA
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20
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Herschbach D. Molecular collisions, from warm to ultracold. Faraday Discuss 2010; 142:9-23; discussion 93-111. [PMID: 20151535 DOI: 10.1039/b910118g] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This introductory article contrasts molecular collisions, particularly reactive collisions, in the familiar "warm" domain with the ultracold regime where the relative deBroglie wavelengths become long compared with the range of interaction of the collision partners. Ultracold collisions have much greater sensitivity to entrance channel interactions, so offer the prospect of tuning by external fields to control onset of reaction. However, for ultracold collisions, kinematic constraints impose severe limitations on the observable dynamical properties. In the exit channel for appreciably exoergic reactions, the deBroglie wavelengths become short, so the exit dynamics are much like those for warm collisions. Reactions of alkali dimers, halides, and monoxide molecules are discussed that seem especially congenial for cold collision studies.
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Affiliation(s)
- Dudley Herschbach
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St., Cambridge, Massachusetts 02138, USA.
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21
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Bargueño P, Gonzalo I, de Tudela RP, Miret-Artés S. Parity violation and critical temperature of non-interacting chiral molecules. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2009.10.086] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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22
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23
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Quéméner G, Balakrishnan N. Quantum calculations of H2–H2 collisions: From ultracold to thermal energies. J Chem Phys 2009; 130:114303. [DOI: 10.1063/1.3081225] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
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24
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Ab-initio calculation of the ground and excited states of MgH using a pseudopotential approach. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2009.01.078] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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25
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26
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Kłos J, Żuchowski PS, Rajchel Ł, Chałasiński G, Szczęśniak MM. Nonadditive interactions in ns2 and spin-polarized ns metal atom trimers. J Chem Phys 2008; 129:134302. [DOI: 10.1063/1.2982801] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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27
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Lodi L, Polyansky O, Tennyson J. On the treatment of long-range interactions in global potential energy surfaces for chemically bound systems. Mol Phys 2008. [DOI: 10.1080/00268970802206442] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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28
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Nagl J, Auböck G, Hauser AW, Allard O, Callegari C, Ernst WE. Heteronuclear and homonuclear high-spin alkali trimers on helium nanodroplets. PHYSICAL REVIEW LETTERS 2008; 100:063001. [PMID: 18352466 DOI: 10.1103/physrevlett.100.063001] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2007] [Indexed: 05/26/2023]
Abstract
The electronic excitation spectra of all possible homo- and heteronuclear high-spin (quartet) trimers of K and Rb (KxRb(3-x), x=0...3) assembled on the surface of superfluid helium droplets, are measured in the spectral range from 10,600 to 17,400 cm(-1). A regular series of corresponding bands is observed, reflecting the similar electronic structure of all these trimers. For the assignment and separation of overlapping bands, we determine x directly, with mass-selected beam depletion, and indirectly with a V-type double-resonance scheme. The assignment is confirmed by high-level ab initio calculations of the electronic structure of the bare trimers. The level structure is rationalized in terms of harmonic-oscillator states of the three valence electrons in a quantum-dot-like confining potential. We predict that three should be a magic number for high-spin alkali clusters.
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Affiliation(s)
- Johann Nagl
- Institute of Experimental Physics, TU Graz, Petersgasse 16, A-8010 Graz, Austria, EU
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29
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Soldán P, Spirko V. Tuning ab initio data to scattering length: The aΣ+3 state of KRb. J Chem Phys 2007; 127:121101. [PMID: 17902885 DOI: 10.1063/1.2790004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Interaction energies for the lowest triplet state a (3)Sigma(+) of KRb are calculated using high level ab initio methods. The interaction energies are then morphed so that the resulting potential energy curve yields 32 bound states and the correct scattering length for (40)K(87)Rb. Calculated vibrational spacings are shown to be in very good agreement with the available experimental Fourier transform and photoassociation vibrational data, but a different numbering scheme has to be used for the experimental vibrational assignment.
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Affiliation(s)
- Pavel Soldán
- Department of Chemical Physics and Optics, Faculty of Mathematics and Physics, Charles University in Prague, Ke Karlovu 3, 12116 Prague 2, Czech Republic.
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30
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Cvitas MT, Soldán P, Hutson JM, Honvault P, Launay JM. Interactions and dynamics in Li+Li2 ultracold collisions. J Chem Phys 2007; 127:074302. [PMID: 17718608 DOI: 10.1063/1.2752162] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A potential energy surface for the lowest quartet electronic state ((4)A(')) of lithium trimer is developed and used to study spin-polarized Li+Li(2) collisions at ultralow kinetic energies. The potential energy surface allows barrierless atom exchange reactions. Elastic and inelastic cross sections are calculated for collisions involving a variety of rovibrational states of Li(2). Inelastic collisions are responsible for trap loss in molecule production experiments. Isotope effects and the sensitivity of the results to details of the potential energy surface are investigated. It is found that for vibrationally excited states, the cross sections are only quite weakly dependent on details of the potential energy surface.
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Affiliation(s)
- Marko T Cvitas
- Department of Chemistry, University of Durham, South Road, Durham DH1 3LE, United Kingdom
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