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Leibin IV, Bezrukov DS, Buchachenko AA. Trapping and thermal migration of the first- and second-row atoms in Ar, Kr and Xe crystals. Phys Chem Chem Phys 2024; 26:958-973. [PMID: 38088087 DOI: 10.1039/d3cp04178f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2024]
Abstract
Trapping and temperature-induced migration (TIM) of the first- and second-row atoms A from H to Ne in the face-centered cubic rare gas RG = Ar, Kr and Xe crystals are investigated within the classical crystal model parameterized by the empirically modified pairwise potentials. New ab initio coupled cluster A-RG potentials computed in a uniform way for all the atoms A are used to represent the atom-crystal interactions. Absolute and relative stabilities of the substitutional and interstitial trapping sites, their structures, interstitial migration pathways, related activation energies and rough estimates of the TIM rates are obtained. The isotropic model, which neglects non-zero atomic electronic orbital momentum, reveals that migration of interstitial atoms along the network of conjugated fcc octahedral voids is the generic case for atomic mobility. Anisotropic interactions with a crystal inherent to P-state atoms B, C, O and F are accounted for using the non-relativistic diatomics-in-molecule method. Depending on its sign, interaction anisotropy can alter the structures of interstitial trapping sites and transition states remarkably. This, in turn, can dramatically affect the TIM rates. Comparison with reliable experimental data available for oxygen and hydrogen indicates a systematic overestimation of the measured activation energies, by 30% at worst. A comprehensive literature review accomplished for other atoms reveals a lack of information on the TIM processes and rates, though makes it possible to verify a part of the present results on the trapping site energies and structures.
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Affiliation(s)
- Iosif V Leibin
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, Moscow 121205, Russia.
| | - Dmitry S Bezrukov
- Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow 119991, Russia
| | - Alexei A Buchachenko
- Skolkovo Institute of Science and Technology, Skolkovo Innovation Center, Moscow 121205, Russia
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2
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Briant M, Mestdagh JM, Gaveau MA, Poisson L. Reaction dynamics within a cluster environment. Phys Chem Chem Phys 2022; 24:9807-9835. [PMID: 35441619 DOI: 10.1039/d1cp05783a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This perspective article reviews experimental and theoretical works where rare gas clusters and helium nanodroplets are used as a nanoreactor to investigate chemical dynamics in a solvent environment. A historical perspective is presented first followed by specific considerations on the mobility of reactants within these reaction media. The dynamical response of pure clusters and nanodroplets to photoexcitation is shortly reviewed before examining the role of the cluster (or nanodroplet) degrees of freedom in the photodynamics of the guest atoms and molecules.
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Affiliation(s)
- Marc Briant
- Université Paris-Saclay, CEA, CNRS, LIDYL, 91191, Gif-sur-Yvette, France
| | | | - Marc-André Gaveau
- Université Paris-Saclay, CEA, CNRS, LIDYL, 91191, Gif-sur-Yvette, France
| | - Lionel Poisson
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d'Orsay, 91405, Orsay, France.
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3
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Dhiman M, Douady J, Gervais B. Geometry, absorption and luminescence of small Ar clusters. Mol Phys 2022. [DOI: 10.1080/00268976.2022.2049905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Mukul Dhiman
- Normandie University, ENSICAEN, UNICAEN, CEA, CNRS, CIMAP, UMR6252, Caen, France
| | - Julie Douady
- Normandie University, ENSICAEN, UNICAEN, CEA, CNRS, CIMAP, UMR6252, Caen, France
| | - Benoit Gervais
- Normandie University, ENSICAEN, UNICAEN, CEA, CNRS, CIMAP, UMR6252, Caen, France
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4
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Somani A, Sander W. Reaction of electrons trapped in cryogenic matrices with benzophenone. J PHYS ORG CHEM 2022. [DOI: 10.1002/poc.4335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ankit Somani
- Lehrstuhl für Organische Chemie II Ruhr‐Universität Bochum Bochum Germany
| | - Wolfram Sander
- Lehrstuhl für Organische Chemie II Ruhr‐Universität Bochum Bochum Germany
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5
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Bezrukov DS, Kleshchina NN, Kalinina IS, Buchachenko AA. Empirically Modified Potentials of Interaction between Rare Gases for Matrix Isolation Problems. Russ J Phys Chem 2019. [DOI: 10.1134/s003602441908003x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Harris N, Sakr AK, Snelling HV, Young NA. X-ray absorption study of platinum and palladium atoms in argon matrices: Evidence for platinum in a substitutional site and a short Pd Ar interaction. J Mol Struct 2018. [DOI: 10.1016/j.molstruc.2018.06.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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7
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Davis B, McCaffrey JG. Luminescence of Atomic Barium in Rare Gas Matrices: A Two-Dimensional Excitation/Emission Spectroscopy Study. J Phys Chem A 2018; 122:7339-7350. [PMID: 30142266 DOI: 10.1021/acs.jpca.8b05140] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A detailed characterization is made of the distinct sites occupied by atomic barium isolated in the three rare gas hosts Ar, Kr, and Xe in excitation scans extracted from the recorded total 6s6p 1P1 → (6s)21S0 fluorescence. Extensive use has been made of two-dimensional excitation/emission (2D-EE) spectroscopy to achieve a comprehensive characterization for the wide variety of sites present in the Ba/RG matrix systems. The 2D-EE technique has proved to be a very powerful method to probe the effects of strong intersite reabsorption when extensive spectral overlap occurs between emission and resonance 6s6p 1P1 ← (6s)21S0 absorption of barium atoms occupying multiple sites. Two-dimensional excitation/emission scans have also been used in this study to monitor the effects of sample annealing and thereby identify the thermally stable sites of isolation. Sites of the same type occupied by atomic barium in the three host solids are identified in resolved excitation spectra and are associated on the basis of the observed matrix shift versus host polarizability. Following site associations, the photophysical properties of each matrix site were characterized revealing that the Stokes shift was greatest in the blue site, smallest for the violet site, and intermediate for the green site. The emission temperature dependences and excited state lifetimes were recorded, indicating that measured radiative lifetimes of 4-5 ns were in good agreement with the gas phase value of 8.4 ns when corrected for the effective field of the solids. The only exception to this was the blue site in Ba/Xe, where a nonradiative quenching channel exists even at 9.8 K that competes effectively with the nanosecond fluorescence. An unusual, asymmetric 2 + 1 excitation band has been recorded for atomic barium in the three rare gas hosts in addition to the threefold split, Jahn-Teller bands typically observed for P ← S absorptions of matrix-isolated metal atoms. Possible assignments of the sites responsible for these band shapes are made on the basis of recent spectral simulations obtained from molecular dynamics calculations on the Ba/Xe system.
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Affiliation(s)
- Barry Davis
- Department of Chemistry , Maynooth University, National University of Ireland , Maynooth , County Kildare , Ireland
| | - John G McCaffrey
- Department of Chemistry , Maynooth University, National University of Ireland , Maynooth , County Kildare , Ireland
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Davis BM, Gervais B, McCaffrey JG. An investigation of the sites occupied by atomic barium in solid xenon-A 2D-EE luminescence spectroscopy and molecular dynamics study. J Chem Phys 2018; 148:124308. [PMID: 29604806 DOI: 10.1063/1.5019890] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
A detailed characterisation of the luminescence recorded for the 6p 1P1-6s 1S0 transition of atomic barium isolated in annealed solid xenon has been undertaken using two-dimensional excitation-emission (2D-EE) spectroscopy. In the excitation spectra extracted from the 2D-EE scans, two dominant thermally stable sites were identified, consisting of a classic, three-fold split Jahn-Teller band, labeled the blue site, and an unusual asymmetric 2 + 1 split band, the violet site. A much weaker band has also been identified, whose emission is strongly overlapped by the violet site. The temperature dependence of the luminescence for these sites was monitored revealing that the blue site has a non-radiative channel competing effectively with the fluorescence even at 9.8 K. By contrast, the fluorescence decay time of the violet site was recorded to be 4.3 ns and independent of temperature up to 24 K. The nature of the dominant thermally stable trapping sites was investigated theoretically with Diatomics-in-Molecule (DIM) molecular dynamics simulations. The DIM model was parameterized with ab initio multi-reference configuration interaction calculations for the lowest energy excited states of the Ba⋅Xe pair. The simulated absorption spectra are compared with the experimental results obtained from site-resolved excitation spectroscopy. The simulations allow us to assign the experimental blue feature spectrum to a tetra-vacancy trapping site in the bulk xenon fcc crystal-a site often observed when trapping other metal atoms in rare gas matrices. By contrast, the violet site is assigned to a specific 5-atom vacancy trapping site located at a grain boundary.
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Affiliation(s)
- Barry M Davis
- Department of Chemistry, Maynooth University, National University of Ireland-Maynooth, County Kildare, Ireland
| | - Benoit Gervais
- Normandie Université, ENSICAEN, UNICAEN, CEA, CNRS, CIMAP, 14000 Caen, France
| | - John G McCaffrey
- Department of Chemistry, Maynooth University, National University of Ireland-Maynooth, County Kildare, Ireland
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Kovács A, Rode JE. Modelling the matrix shift on the vibrational frequency of ThO by DFT-D3 calculations. J Chem Phys 2017; 146:124301. [PMID: 28388137 DOI: 10.1063/1.4978064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Benchmark calculations with a goal to find dispersion-corrected DFT-D3 methods suitable for a reliable estimation of matrix shifts on the vibrational frequency were carried out on the ThO molecule in three rare gas (Rg = Ne, Ar, and Kr) matrices. The matrices were modelled by the explicit approach, in which a single and a double shell of Rg atoms around ThO was considered. The selection of exchange-correlation functionals was based on test calculations on triatomic ThO⋯Rg models. The B3LYP, PBE0, CAM-B3LYP, and LC-ωPBE functionals were found to be the best suited for the estimation of matrix shifts. The single shell of Rg's around ThO accounted for a major part of the shifts; the addition of a second Rg shell resulted only in a minor improvement. Continuum solvation models considerably overestimated the effect of Rg matrices both when the whole matrix was treated by the model and when the first shell was treated explicitly and the rest with a continuum solvation model.
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Affiliation(s)
- Attila Kovács
- European Commission, Joint Research Centre, P.O. Box 2340, 76125 Karlsruhe, Germany
| | - Joanna E Rode
- Institute of Nuclear Chemistry and Technology, 16 Dorodna-Street, 03-195 Warsaw, Poland
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Gervais B, Zanuttini D, Douady J. Spin-orbit coupling in the dissociative excitation of alkali atoms at the surface of rare gas clusters: A theoretical study. J Chem Phys 2016; 144:194307. [PMID: 27208949 DOI: 10.1063/1.4948814] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
We analyze the role of the spin-orbit (SO) coupling in the dissociative dynamics of excited alkali atoms at the surface of small rare gas clusters. The electronic structure of the whole system is deduced from a one-electron model based on core polarization pseudo-potentials. It allows us to obtain in the same footing the energy, forces, and non-adiabatic couplings used to simulate the dynamics by means of a surface hopping method. The fine structure state population is analyzed by considering the relative magnitude of the SO coupling ξ, with respect to the spin-free potential energy. We identify three regimes of ξ-values leading to different evolution of adiabatic state population after excitation of the system in the uppermost state of the lowest np (2)P shell. For sufficiently small ξ, the final population of the J=12 atomic states, P12, grows up linearly from P12=13 at ξ = 0 after a diabatic dynamics. For large values of ξ, we observe a rather adiabatic dynamics with P12 decreasing as ξ increases. For intermediate values of ξ, the coupling is extremely efficient and a complete transfer of population is observed for the set of parameters associated to NaAr3 and NaAr4 clusters.
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Affiliation(s)
- B Gervais
- CIMAP, Unité Mixte CEA-CNRS-ENSICAEN-UCBN 6252 BP 5133, F-14070 Caen Cedex 05, France
| | - D Zanuttini
- CIMAP, Unité Mixte CEA-CNRS-ENSICAEN-UCBN 6252 BP 5133, F-14070 Caen Cedex 05, France
| | - J Douady
- CIMAP, Unité Mixte CEA-CNRS-ENSICAEN-UCBN 6252 BP 5133, F-14070 Caen Cedex 05, France
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Tao LG, Kleshchina NN, Lambo R, Buchachenko AA, Zhou XG, Bezrukov DS, Hu SM. Heat- and light-induced transformations of Yb trapping sites in an Ar matrix. J Chem Phys 2015; 143:174306. [PMID: 26547169 DOI: 10.1063/1.4934999] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The low-lying electronic states of Yb isolated in a solid Ar matrix grown at 4.2 K are characterized through absorption and emission spectroscopy. Yb atoms are found to occupy three distinct thermally stable trapping sites labeled "red," "blue," and "violet" according to the relative positions of the absorption features they produce. Classical simulations of the site structure and relative stability broadly reproduced the experimentally observed matrix-induced frequency shifts and thus identified the red, blue, and violet sites as due to respective single substitutional (ss), tetravacancy (Tv), and hexavacancy (Hv) occupation. Prolonged excitation of the (1)S → (1)P transition was found to transfer the Yb population from hv sites into Tv and ss sites. The process showed reversibility in that annealing to 24 K predominantly transferred the Tv population back into Hv sites. Population kinetics were used to deduce the effective rate parameters for the site transformation processes. Experimental observations indicate that the blue and violet sites lie close in energy, whereas the red one is much less stable. Classical simulations identify the blue site as the most stable one.
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Affiliation(s)
- L-G Tao
- Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei 230026, China
| | - N N Kleshchina
- Department of Chemistry, M. V. Lomonosov Moscow State University, Moscow 119991, Russia
| | - R Lambo
- Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei 230026, China
| | - A A Buchachenko
- Skolkovo Institute of Science and Technology, 100 Novaya St., Skolkovo, Moscow Region 143025, Russia
| | - X-G Zhou
- Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei 230026, China
| | - D S Bezrukov
- Department of Chemistry, M. V. Lomonosov Moscow State University, Moscow 119991, Russia
| | - S-M Hu
- Hefei National Laboratory for Physical Sciences at the Microscale, Collaborative Innovation Center of Chemistry for Energy Materials, University of Science and Technology of China, Hefei 230026, China
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Awali S, Poisson L, Rhouma MBEH, Mestdagh JM. Absorption Spectroscopy, a Tool for Probing Local Structures and the Onset of Large-Amplitude Motions in Small KAr(n) Clusters at Increasing Temperatures. J Phys Chem A 2015; 119:9729-38. [PMID: 26301681 DOI: 10.1021/acs.jpca.5b07192] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Photoabsorption spectra of KArn (n = 1-10) are simulated at temperatures ranging between 5 and 25 K. The calculations associate a Monte Carlo (MC) method to sample cluster geometries at temperature T, with a one-electron ab initio model to calculate the ground-state and excited-state energies of the cluster. The latter model replaces the K(+) core electrons and all the electrons of the Ar atoms by appropriate pseudopotentials, complemented by core polarization potentials. It also provides the necessary oscillator strengths to simulate the spectra. Global optimization by basin-hopping is used in combination with MC simulation at low temperature (5 K) to identify the most stable isomer and remarkable isomers of ground-state KArn clusters, which are stable with respect to deformations of the order of those expected with Zero Point Energy motions. The absorption spectra calculated for each of these isomers at 5 K suggest that absorption spectroscopy can probe sensitively the local environment of K atom: surface location of K with respect to a close-packed Ar moiety, number of Ar atom in close vicinity, and local symmetry about K. Simulation at increasing temperatures, up to the evaporation limit of K out of the cluster, shows the onset of large amplitude motions above 20 K, when the K atom experiences a variety of local environments.
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Affiliation(s)
- Slim Awali
- Laboratoire Francis Perrin, URA 2453, CEA/IRAMIS/LIDyL , F-91191 Gif-sur-Yvette Cedex, France.,Laboratoire Francis Perrin, URA 2453, CNRS/IRAMIS/LIDyL , F-91191 Gif-sur-Yvette Cedex, France.,Laboratoire d'Etudes des Milieux Ionisés et Réactifs (EMIR), Institut Préparatoire aux Etudes d'Ingénieurs , Monastir, Tunisia
| | - Lionel Poisson
- Laboratoire Francis Perrin, URA 2453, CEA/IRAMIS/LIDyL , F-91191 Gif-sur-Yvette Cedex, France.,Laboratoire Francis Perrin, URA 2453, CNRS/IRAMIS/LIDyL , F-91191 Gif-sur-Yvette Cedex, France
| | - Mounir Ben El Hadj Rhouma
- Laboratoire d'Etudes des Milieux Ionisés et Réactifs (EMIR), Institut Préparatoire aux Etudes d'Ingénieurs , Monastir, Tunisia
| | - Jean-Michel Mestdagh
- Laboratoire Francis Perrin, URA 2453, CEA/IRAMIS/LIDyL , F-91191 Gif-sur-Yvette Cedex, France.,Laboratoire Francis Perrin, URA 2453, CNRS/IRAMIS/LIDyL , F-91191 Gif-sur-Yvette Cedex, France
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Abstract
We present a combined experimental and simulation study of the 4s → 4p photoexcitation of the K atom trapped at the surface of ArN clusters made of a few hundred Ar atoms. Our experimental method based on photoelectron spectroscopy allows us to firmly establish that one single K atom is trapped at the surface of the cluster. The absorption spectrum is characterized by the splitting of the atomic absorption line into two broad bands, a Π band associated with p orbitals parallel to the cluster surface and a Σ band associated with the perpendicular orientation. The spectrum is consistent with observations reported for K atoms trapped on lighter inert gas clusters, but the splitting between the Π and Σ bands is significantly larger. We show that a large amount of K atoms are transiently stuck and eventually lost by the Ar cluster, in contrast with previous observations reported for alkaline earth metal systems. The excitation in the Σ band leads systematically to the ejection of the K atom from the Ar cluster. On the contrary, excitation in the Π band leads to the formation of a bound state. In this case, the analysis of the experimental photoelectron spectrum by means of nonadiabatic molecular dynamics simulation shows that the relaxation drives the system toward a basin where the coordination of the K atom is 2.2 Ar atoms on the average, in a poorly structured surface.
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Affiliation(s)
- J Douady
- †Unité mixte CEA-CNRS-ENSICAEN-UCBN 6252 BP 5133, CIMAP, F-14070 Caen, Cedex 05, France
| | - S Awali
- ‡Laboratoire Francis Perrin, URA 2453, CEA/IRAMIS/LIDYL, F-91191 Gif-sur-Yvette, France.,§EMIR, Institut Préparatoire aux Etudes d'Ingénieurs de Monastir (IPEIM), 5019 Monastir, Tunisie
| | - L Poisson
- ∥Laboratoire Francis Perrin, URA 2453, CNRS/IRAMIS/LIDYL, F-91191 Gif-sur-Yvette, France
| | - B Soep
- ∥Laboratoire Francis Perrin, URA 2453, CNRS/IRAMIS/LIDYL, F-91191 Gif-sur-Yvette, France
| | - J M Mestdagh
- ∥Laboratoire Francis Perrin, URA 2453, CNRS/IRAMIS/LIDYL, F-91191 Gif-sur-Yvette, France
| | - B Gervais
- †Unité mixte CEA-CNRS-ENSICAEN-UCBN 6252 BP 5133, CIMAP, F-14070 Caen, Cedex 05, France
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Lozada-García R, Rojas-Lorenzo G, Crépin C, Ryan M, McCaffrey JG. Hg-Xe exciplex formation in mixed Xe/Ar matrices: molecular dynamics and luminescence study. J Phys Chem A 2015; 119:2307-17. [PMID: 25233130 DOI: 10.1021/jp5065038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Luminescence of Hg((3)P1) atoms trapped in mixed Ar/Xe matrices containing a small amount of Xe is reported. Broad emission bands, strongly red-shifted from absorption are recorded which are assigned to strong complexes formed between the excited mercury Hg* and xenon atoms. Molecular dynamics calculations are performed on simulated Xe/Ar samples doped with Hg to follow the behavior of Hg* in the mixed rare gas matrices leading to exciplex formation. The role of Xe atoms in the first solvation shell (SS1) around Hg was investigated in detail, revealing the formation of two kinds of triatomic exciplexes; namely, Xe-Hg*-Xe and Ar-Hg*-Xe. The first species exists only when two xenon atoms are present in SS1 with specific geometries allowing the formation of a linear or quasi-linear exciplex. In the other geometries, or in the presence of only one Xe in SS1, a linear Ar-Hg*-Xe exciplex is formed. The two kinds of exciplexes have different emission bands, the most red-shifted being that involving two Xe atoms, whose emission is very close to that observed in pure Xe matrices. Simulations give a direct access to the analysis of the experimental absorption, emission, and excitation spectra, together with the dynamics of exciplexes formation.
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Affiliation(s)
- Rolando Lozada-García
- †Departamento de Física General, Matemática y Computación, Instituto Superior de Tecnologías y Ciencias Aplicadas, La Habana, Cuba
| | - Germán Rojas-Lorenzo
- †Departamento de Física General, Matemática y Computación, Instituto Superior de Tecnologías y Ciencias Aplicadas, La Habana, Cuba
| | - Claudine Crépin
- ‡Institut des Sciences Moléculaires d'Orsay (ISMO)- UMR 8214, CNRS-Université Paris-Sud, Bâtiment 210 Université Paris-Sud, F-91405 Orsay, France
| | - Maryanne Ryan
- §Department of Chemistry, National University of Ireland-Maynooth, Maynooth, Co., Kildare, Ireland
| | - John G McCaffrey
- §Department of Chemistry, National University of Ireland-Maynooth, Maynooth, Co., Kildare, Ireland
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Simon A, Iftner C, Mascetti J, Spiegelman F. Water clusters in an argon matrix: infrared spectra from molecular dynamics simulations with a self-consistent charge density functional-based tight binding/force-field potential. J Phys Chem A 2015; 119:2449-67. [PMID: 25650885 DOI: 10.1021/jp508533k] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The present theoretical study aims at investigating the effects of an argon matrix on the structures, energetics, dynamics, and infrared (IR) spectra of small water clusters (H2O)n (n = 1-6). The potential energy surface is obtained from a hybrid self-consistent charge density functional-based tight binding/force-field approach (SCC-DFTB/FF) in which the water clusters are treated at the SCC-DFTB level and the matrix is modeled at the FF level by a cluster consisting of ∼340 Ar atoms with a face centered cubic (fcc) structure, namely (H2O)n/Ar. With respect to a pure FF scheme, this allows a quantum description of the molecular system embedded in the matrix, along with all-atom geometry optimization and molecular dynamics (MD) simulations of the (H2O)n/Ar system. Finite-temperature IR spectra are derived from the MD simulations. The SCC-DFTB/FF scheme is first benchmarked on (H2O)Arn clusters against correlated wave function results and DFT calculations performed in the present work, and against FF data available in the literature. Regarding (H2O)n/Ar systems, the geometries of the water clusters are found to adapt to the fcc environment, possibly leading to intermolecular distortion and matrix perturbation. Several energetical quantities are estimated to characterize the water clusters in the matrix. In the particular case of the water hexamer, substitution and insertion energies for the prism, bag, and cage are found to be lower than that for the 6-member ring isomer. Finite-temperature MD simulations show that the water monomer has a quasifree rotation motion at 13 K, in agreement with experimental data. In the case of the water dimer, the only large-amplitude motion is a distortion-rotation intermolecular motion, whereas only vibration motions around the nuclei equilibrium positions are observed for clusters with larger sizes. Regarding the IR spectra, we find that the matrix environment leads to redshifts of the stretching modes and almost no shift of the bending modes. This is in agreement with experimental data. Furthermore, in the case of the water monomer and dimer, the magnitudes of the computed shifts are in fair agreement with the experimental values. The complex case of the water hexamer, which presents several low-energy isomers, is discussed.
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Affiliation(s)
- Aude Simon
- †Laboratoire de Chimie et Physique Quantiques LCPQ/IRSAMC, Université de Toulouse (UPS) and CNRS, 118 Route de Narbonne, F-31062 Toulouse, France
| | - Christophe Iftner
- †Laboratoire de Chimie et Physique Quantiques LCPQ/IRSAMC, Université de Toulouse (UPS) and CNRS, 118 Route de Narbonne, F-31062 Toulouse, France
| | - Joëlle Mascetti
- ‡Institut des Sciences Moléculaires, Université de Bordeaux and CNRS, 351 Cours de la Libération, 33405 Talence cedex, France
| | - Fernand Spiegelman
- †Laboratoire de Chimie et Physique Quantiques LCPQ/IRSAMC, Université de Toulouse (UPS) and CNRS, 118 Route de Narbonne, F-31062 Toulouse, France
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Iftner C, Simon A, Korchagina K, Rapacioli M, Spiegelman F. A density functional tight binding/force field approach to the interaction of molecules with rare gas clusters: Application to (C6H6)+/0Arn clusters. J Chem Phys 2014; 140:034301. [DOI: 10.1063/1.4861431] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Galbis E, Douady J, Jacquet E, Giglio E, Gervais B. Potential energy curves and spin-orbit coupling of light alkali-heavy rare gas molecules. J Chem Phys 2013; 138:014314. [PMID: 23298048 DOI: 10.1063/1.4773019] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The potential energy curves of the X, A, and B states of alkali-rare gas diatomic molecules, MKr and MXe, are investigated for M = Li, Na, K. The molecular spin-orbit coefficients a(R)=<(2)Π(½)|Ĥ(SO)|(2)Π(½)> and b(R)=<(2)Π(-½)|Ĥ(SO)|(2)Σ(½)> are calculated as a function the interatomic distance R. We show that a(R) increases and b(R) decreases as R decreases. This effect becomes less and less important as the mass of the alkali increases. A comparison of the rovibrational properties deduced from our calculations with experimental measurements recorded for NaKr and NaXe shows the quality of the calculations.
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Affiliation(s)
- E Galbis
- CIMAP, unité mixte CEA-CNRS-ENSICAEN-UCBN 6252 BP 5133, F-14070 Caen, Cedex 05, France
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Salem FB, Rhouma MBEH, Spiegelman F, Mestdagh JM, Hochlaf M. Theoretical investigations of the electronic states of NaXe: A comparative study. J Chem Phys 2012; 137:224310. [DOI: 10.1063/1.4769286] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
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