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Alioua K. Theoretical study of the spin-orbit coupled molecular states of the Mg-He dimer. Phys Chem Chem Phys 2024; 26:17090-17101. [PMID: 38842191 DOI: 10.1039/d4cp01128g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2024]
Abstract
The primary objective of this study is to conduct precise ab initio calculations of the spin-orbit interaction between Mg and He atoms. Our investigation centers on identifying the first low-lying electronic states of the Mg-He molecule through high-level theoretical methods such as CCSD(T) and RCCSD(T) and SA-CASSCF/MRCI, while also integrating Davidson and BSSE corrections to refine our findings further. Additionally, we employ the state-interacting method to comprehensively account for the influence of spin-orbit coupling (SO) on molecular states. We carefully characterize the potential energy curves (PECs) of these molecular states by deriving crucial spectroscopic parameters including Re, De, Be and Te, which are then compared against data from prior studies. Moreover, our analysis extends to evaluating vibrational levels, radiative lifetimes, and transition dipole moments (TDMs), offering a comprehensive understanding of the system's dynamics. Notably, we locate the positions of satellite features within the absorption spectra of brown and white dwarfs. To validate the precision and reliability of our findings, extensive comparisons are made with both theoretical predictions and experimental observations, ensuring robustness and accuracy in our conclusions.
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Affiliation(s)
- K Alioua
- Chérif Messaidia University, and Laboratoire de Physique de la Matière et du Rayonnement, B.P. 1553, Souk-Ahras 41000, Algeria.
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2
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Rendler N, Scognamiglio A, Barranco M, Pí M, Halberstadt N, Dulitz K, Stienkemeier F. Dynamics of Photoexcited Cs Atoms Attached to Helium Nanodroplets. J Phys Chem A 2021; 125:9048-9059. [PMID: 34619968 DOI: 10.1021/acs.jpca.1c05467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present an experimental study of the dynamics following the photoexcitation and subsequent photoionization of single Cs atoms on the surface of helium nanodroplets. The dynamics of excited Cs atom desorption and readsorption as well as CsHe exciplex formation are measured by using femtosecond pump-probe velocity map imaging spectroscopy and ion time-of-flight spectrometry. The time scales for the desorption of excited Cs atoms off helium nanodroplets as well as the time scales for CsHe exciplex formation are experimentally determined for the 6p states of Cs. For the 6p 2Π1/2 state, our results confirm that the excited Cs atoms only desorb from the nanodroplet when the excitation wavenumber is blue-shifted from the 6p 2Π1/2 ← 6s 2Σ1/2 resonance. Our results suggest that the dynamics following excitation to the 6p 2Π3/2 state can be described by an evaporation-like desorption mechanism, whereas the dynamics arising from excitation to the 6p 2Σ1/2 state is indicative for a more impulsive desorption process. Furthermore, our results suggest a helium-induced spin-orbit relaxation from the 6p 2Σ1/2 state to the 6p 2Π1/2 state. Our findings largely agree with the results of time-dependent 4He density functional theory (DFT) simulations published earlier [Eur. Phys. J. D 2019, 73, 94].
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Affiliation(s)
- Nicolas Rendler
- Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany
| | - Audrey Scognamiglio
- Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany
| | - Manuel Barranco
- Laboratoire des Collisions, Agrégats, Réactivité, IRSAMC, Université de Toulouse, CNRS UMR 5589, 118 route de Narbonne, 31062 Toulouse Cedex 09, France.,Departament FQA, Facultat de Física, Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Spain.,Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Spain
| | - Marti Pí
- Departament FQA, Facultat de Física, Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Spain.,Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Spain
| | - Nadine Halberstadt
- Laboratoire des Collisions, Agrégats, Réactivité, IRSAMC, Université de Toulouse, CNRS UMR 5589, 118 route de Narbonne, 31062 Toulouse Cedex 09, France
| | - Katrin Dulitz
- Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany
| | - Frank Stienkemeier
- Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg, Germany
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3
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Martinez M, Coppens F, Barranco M, Halberstadt N, Pi M. 4s to 5s and 4p photoexcitation dynamics of K atoms from the surface of helium nanodroplets: a theoretical study. Phys Chem Chem Phys 2019; 21:3626-3636. [DOI: 10.1039/c8cp05253k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We study the photodissociation of the potassium atom from a superfluid helium nanodroplet upon 5s 2S or 4p 2P excitation using the time-dependent helium density functional method (He-TDDFT). The results show possible K spin–orbit relaxation.
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Affiliation(s)
- Maxime Martinez
- Laboratoire Collisions Agrégats Réactivité (LCAR)
- IRSAMC
- Université de Toulouse
- CNRS UMR 5589
- Toulouse
| | - François Coppens
- Laboratoire Collisions Agrégats Réactivité (LCAR)
- IRSAMC
- Université de Toulouse
- CNRS UMR 5589
- Toulouse
| | - Manuel Barranco
- Laboratoire Collisions Agrégats Réactivité (LCAR)
- IRSAMC
- Université de Toulouse
- CNRS UMR 5589
- Toulouse
| | - Nadine Halberstadt
- Laboratoire Collisions Agrégats Réactivité (LCAR)
- IRSAMC
- Université de Toulouse
- CNRS UMR 5589
- Toulouse
| | - Martí Pi
- Departament FQA
- Facultat de Física
- Universitat de Barcelona. Diagonal 645
- 08028 Barcelona
- Spain
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Messner R, Schiffmann A, Pototschnig JV, Lasserus M, Schnedlitz M, Lackner F, Ernst WE. Spectroscopy of gold atoms and gold oligomers in helium nanodroplets. J Chem Phys 2018; 149:024305. [PMID: 30007398 DOI: 10.1063/1.5026480] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The 6p 2P1/2 ← 6s 2S1/2 and 6p 2P3/2 ← 6s 2S1/2 transitions (D lines) of gold atoms embedded in superfluid helium nanodroplets have been investigated using resonant two-photon ionization spectroscopy. Both transitions are strongly blue-shifted and broadened due to the repulsive interaction between the Au valence electron and the surrounding helium. The in-droplet D lines are superimposed by the spectral signature of Au atoms relaxed into the metastable 2D states. These features are narrower than the in-droplet D lines and exhibit sharp rising edges that coincide with bare atom transitions. It is concluded that they originate from metastable 2D state AuHen exciplexes that have been ejected from the helium droplets during a relaxation process. Interestingly, the mechanism that leads to the formation of these complexes is suppressed for very large helium droplets consisting of about 2 × 106 He atoms, corresponding to a droplet diameter on the order of 50 nm. The assignment of the observed spectral features is supported by ab initio calculations employing a multiconfigurational self-consistent field method and a multi-reference configuration interaction calculation. For large helium droplets doped with Au oligomers, excitation spectra for mass channels corresponding to Aun with n = 2, 3, 4, 5, 7, and 9 are presented. The mass spectrum reveals even-odd oscillations in the number of Au atoms that constitute the oligomer, which is characteristic for coinage metal clusters. Resonances are observed close by the in-droplet D1 and D2 transitions, and the corresponding peak forms are very similar for different oligomer sizes.
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Affiliation(s)
- Roman Messner
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Alexander Schiffmann
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Johann V Pototschnig
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Maximilian Lasserus
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Martin Schnedlitz
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Florian Lackner
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Wolfgang E Ernst
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz, Austria
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Vindel Zandbergen P, Barranco M, Cargnoni F, Drabbels M, Pi M, Halberstadt N. Helium-induced electronic transitions in photo-excited Ba+–Hen exciplexes. J Chem Phys 2018; 148:144302. [DOI: 10.1063/1.5022863] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Patricia Vindel Zandbergen
- Laboratoire Collisions Agrégats Réactivité (LCAR), IRSAMC, Université de Toulouse, CNRS UMR 5589, Toulouse, France
| | - Manuel Barranco
- Laboratoire Collisions Agrégats Réactivité (LCAR), IRSAMC, Université de Toulouse, CNRS UMR 5589, Toulouse, France
- Departament FQA, Facultat de Física, Universitat de Barcelona, Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, Spain
| | | | - Marcel Drabbels
- Laboratory of Molecular Nanodynamics, Swiss Federal Institute of Technology Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Martí Pi
- Departament FQA, Facultat de Física, Universitat de Barcelona, Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, Spain
| | - Nadine Halberstadt
- Laboratoire Collisions Agrégats Réactivité (LCAR), IRSAMC, Université de Toulouse, CNRS UMR 5589, Toulouse, France
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Ancilotto F, Barranco M, Coppens F, Eloranta J, Halberstadt N, Hernando A, Mateo D, Pi M. Density functional theory of doped superfluid liquid helium and nanodroplets. INT REV PHYS CHEM 2017. [DOI: 10.1080/0144235x.2017.1351672] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Francesco Ancilotto
- Dipartimento di Fisica e Astronomia ‘Galileo Galilei’ and CNISM, Università di Padova, Padova, Italy
- CNR-IOM Democritos, Trieste, Italy
| | - Manuel Barranco
- Facultat de Física, Departament FQA, Universitat de Barcelona, Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, Spain
- Laboratoire des Collisions, Agrégats et Réactivité, IRSAMC, Université Toulouse 3 and CNRS, Toulouse Cedex 09, France
| | - François Coppens
- Laboratoire des Collisions, Agrégats et Réactivité, IRSAMC, Université Toulouse 3 and CNRS, Toulouse Cedex 09, France
| | - Jussi Eloranta
- Department of Chemistry and Biochemistry, California State University at Northridge, Northridge, CA, USA
| | - Nadine Halberstadt
- Laboratoire des Collisions, Agrégats et Réactivité, IRSAMC, Université Toulouse 3 and CNRS, Toulouse Cedex 09, France
| | - Alberto Hernando
- Social Thermodynamics Applied Research (SThAR), EPFL Innovation Park, Lausanne, Switzerland
| | - David Mateo
- Applied Complexity Group, Singapore University of Technology and Design, Singapore, Singapore
| | - Martí Pi
- Facultat de Física, Departament FQA, Universitat de Barcelona, Barcelona, Spain
- Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, Barcelona, Spain
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Seki Y, Takayanagi T, Shiga M. Photoexcited Ag ejection from a low-temperature He cluster: a simulation study by nonadiabatic Ehrenfest ring-polymer molecular dynamics. Phys Chem Chem Phys 2017; 19:13798-13806. [DOI: 10.1039/c7cp00888k] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nonadiabatic ring-polymer molecular dynamics simulations were performed to understand the photoexcitation dynamics of a low-temperature Ag·He500 cluster.
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Affiliation(s)
- Yusuke Seki
- Department of Chemistry
- Saitama University
- Saitama City
- Japan
| | | | - Motoyuki Shiga
- Center for Computational Science and E-Systems
- Japan Atomic Energy Agency
- Kashiwa
- Japan
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Coppens F, Ancilotto F, Barranco M, Halberstadt N, Pi M. Capture of Xe and Ar atoms by quantized vortices in4He nanodroplets. Phys Chem Chem Phys 2017; 19:24805-24818. [DOI: 10.1039/c7cp03307a] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a computational study, based on time-dependent Density Functional theory, of the real-time interaction and trapping of Ar and Xe atoms in superfluid4He nanodroplets either pure or hosting quantized vortex lines.
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Affiliation(s)
- François Coppens
- Université de Toulouse
- UPS
- Laboratoire Collisions Agrégats Réactivité
- IRSAMC
- F-31062 Toulouse
| | - Francesco Ancilotto
- Dipartimento di Fisica e Astronomia ‘Galileo Galilei’ and CNISM
- Università di Padova
- 35122 Padova
- Italy
- CNR-IOM Democritos
| | - Manuel Barranco
- Université de Toulouse
- UPS
- Laboratoire Collisions Agrégats Réactivité
- IRSAMC
- F-31062 Toulouse
| | - Nadine Halberstadt
- Université de Toulouse
- UPS
- Laboratoire Collisions Agrégats Réactivité
- IRSAMC
- F-31062 Toulouse
| | - Martí Pi
- Facultat de Física
- Departament FQA
- Universitat de Barcelona
- 08028 Barcelona
- Spain
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Bonifaci N, Li Z, Eloranta J, Fiedler SL. Interaction of Helium Rydberg State Molecules with Dense Helium. J Phys Chem A 2016; 120:9019-9027. [PMID: 27783517 DOI: 10.1021/acs.jpca.6b08412] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The interaction potentials of the He2* excimer, in the a3Σu, b3Πg, c3Σg, and d3Σu electronic states with a ground state helium atom are presented. The symmetry of the interaction potentials closely follows the excimer Rydberg electron density with pronounced short-range minima appearing along the nodal planes of the Rydberg orbital. In such cases, a combination of the electrostatic short-range attraction combined with Pauli repulsion leads to the appearance of unusual long-range maxima in the potentials. Bosonic density functional calculations show that the 3d state excimer resides in a localized solvation bubble in dense helium at 4.5 K, with radii varying from 12.7 Å at 0.1 MPa to 10.8 Å at 2.4 MPa. The calculated 3d → 3b pressure-induced fluorescence band shifts are in good agreement with experimental results determined by application of corona discharge. The magnitude of the spectral shifts indicate that the observed He2* molecules emit from dense helium whereas the corresponding fluorescence signal from the discharge zone appears quenched. This implies that fluorescence spectroscopy involving this electronic transition can only be used to probe the state of the surrounding medium rather than the discharge zone itself.
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Affiliation(s)
- Nelly Bonifaci
- G2ELab-GreEn-ER, Equipe MDE , 21 avenue des Martyrs, CS 90624, 38031 Grenoble Cedex 1, France
| | - Zhiling Li
- Guizhou Institute of Technology 1 Caiguan Road, 550003 Guiyang, China
| | - Jussi Eloranta
- Department of Chemistry and Biochemistry, California State University at Northridge , 18111 Nordhoff St., Northridge, California 91330, United States
| | - Steven L Fiedler
- Department of Biology and Chemistry, Fitchburg State University , 160 Pearl St., Fitchburg, Massachusetts 01420, United States
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