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Xian SY, Tan DH, Li AY. On the bonding nature of noble gas compounds MRg+ and MRgF (M=Co, Rh, Ir; Rg=Ar, Kr, Xe). CHINESE J CHEM PHYS 2021. [DOI: 10.1063/1674-0068/cjcp2009174] [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]
Affiliation(s)
- Si-yuan Xian
- School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - Di-hao Tan
- School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
| | - An-yong Li
- School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China
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2
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Ryazantsev SV, Lundell J, Feldman VI, Khriachtchev L. Photochemistry of the H 2O/CO System Revisited: The HXeOH···CO Complex in a Xenon Matrix. J Phys Chem A 2018; 122:159-166. [PMID: 29206459 DOI: 10.1021/acs.jpca.7b10293] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report on the complex of a noble-gas hydride HXeOH with carbon monoxide. This species is prepared via the annealing-induced H + Xe + OH···CO reaction in a xenon matrix, the OH···CO complexes being produced by VUV photolysis of the H2O···CO complexes. The H-Xe stretching mode of the HXeOH···CO complex absorbs at 1590.3 cm-1 and it is blue-shifted by 12.7 cm-1 from the H-Xe stretching band of HXeOH monomer. The observed blue shift indicates the stabilization of the H-Xe bond upon complexation, which is characteristic of complexes of noble-gas hydrides. The HXeOH···CO species is the first complex of a noble-gas hydride with carbon monoxide and the second observed complex of HXeOH. On the basis of the MP2/aug-cc-pVTZ-PP calculations, the experimental complex is assigned to the structure, where the carbon atom of CO interacts with the oxygen atom of HXeOH.
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Affiliation(s)
- Sergey V Ryazantsev
- Department of Chemistry, University of Helsinki , P.O. Box 55, FI-00014 Helsinki, Finland.,Department of Chemistry, Lomonosov Moscow State University , Moscow 119991 Russia
| | - Jan Lundell
- Department of Chemistry, University of Jyväskylä , Jyväskylä, FI-40014, Finland
| | - Vladimir I Feldman
- Department of Chemistry, Lomonosov Moscow State University , Moscow 119991 Russia
| | - Leonid Khriachtchev
- Department of Chemistry, University of Helsinki , P.O. Box 55, FI-00014 Helsinki, Finland
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3
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Cohen A, Gerber RB. A Noble-Gas Hydride in a Nitrogen Medium: Structure, Spectroscopy, and Intermolecular Vibrations of HXeBr@(N2)22. J Phys Chem A 2016; 120:3372-9. [PMID: 27018537 DOI: 10.1021/acs.jpca.6b01476] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Noble-gas hydrides have been extensively studied in noble gas matrices. However, little is known on their stability and properties in molecular hosts. Here, HXeBr in the N2 environment is modeled at the B3LYP-D level of theory in a complete single shell of 22 N2 molecules. The system is compared to similar models of HXeBr in CO2 and Xe clusters. The optimized structure of (HXeBr)@(N2)22 is of low symmetry and is highly anisotropic. None of the N2 molecules are freely rotating, and the host molecules are not symmetrically positioned with respect to the HXeBr axis. The axes of the N2 molecules are nonuniformly distributed. The computed anharmonic H-Xe stretching frequency of HXeBr in the N2 cluster is in good accord with the experimental value. The soft-mode frequencies of the cluster including both intermolecular vibrations and librations, have a broad distribution that ranges from 8.7 to 107 cm(-1). It is expected that these findings and specifically, the single-shell model, may shed light also on the local structure and vibrations of other impurities in a molecular media.
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Affiliation(s)
- Arik Cohen
- Institute of Chemistry and The Fritz Haber Center for Molecular Dynamics, The Hebrew University , Jerusalem 91904, Israel
| | - Robert Benny Gerber
- Institute of Chemistry and The Fritz Haber Center for Molecular Dynamics, The Hebrew University , Jerusalem 91904, Israel.,Department of Chemistry, University of Helsinki , P.O. Box 55, Helsinki, FIN-00014, Finland.,Department of Chemistry, University of California , Irvine, California 92697, United States
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4
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Kinetics and mechanism of the radiation-chemical synthesis of krypton hydrides in solid krypton matrices. Radiat Phys Chem Oxf Engl 1993 2015. [DOI: 10.1016/j.radphyschem.2015.01.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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5
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Niimi K, Taketsugu T, Nakayama A. Matrix site effects on vibrational frequencies of HXeCCH, HXeBr, and HXeI: a hybrid quantum-classical simulation. Phys Chem Chem Phys 2015; 17:7872-80. [PMID: 25716235 DOI: 10.1039/c5cp00568j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The matrix shifts of the H-Xe stretching frequency of noble-gas hydrides, HXeCCH, HXeBr, and HXeI in various noble-gas matrices (in Ne, Ar, Kr, and Xe matrices) are investigated via the hybrid quantum-classical simulations. The order of the H-Xe stretching frequencies is found to be ν(gas) < ν(Ne) < ν(Xe) < ν(Kr) < ν(Ar) for HXeCCH and HXeBr, while it is ν(gas) < ν(Ne) < ν(Xe) < ν(Ar) < ν(Kr) for HXeI. This order is anomalous with respect to the matrix dielectric constants, and the calculated results reproduce the experimentally observed shifts quite successfully. We also find that the matrix shifts from the gas-phase values are Δν(HXeCCH) ≈ Δν(HXeCl) < Δν(HXeBr) < Δν(HXeI) in the same noble-gas matrix environments, which implies that the weakly bound molecules exhibit large matrix shifts. The local trapping site is analyzed in detail, and it is shown that a realistic modeling of the surrounding matrix environments is essential to describe the unusual matrix shifts accurately.
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Affiliation(s)
- Keisuke Niimi
- Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-0810, Japan
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6
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Zhu C, Niimi K, Taketsugu T, Tsuge M, Nakayama A, Khriachtchev L. HXeI and HXeH in Ar, Kr, and Xe matrices: Experiment and simulation. J Chem Phys 2015; 142:054305. [DOI: 10.1063/1.4906875] [Citation(s) in RCA: 10] [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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7
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Kalinowski J, Gerber RB, Räsänen M, Lignell A, Khriachtchev L. Matrix effect on vibrational frequencies: Experiments and simulations for HCl and HNgCl (Ng = Kr and Xe). J Chem Phys 2014; 140:094303. [DOI: 10.1063/1.4866913] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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8
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Tsuge M, Berski S, Räsänen M, Latajka Z, Khriachtchev L. Matrix-isolation and computational study of the HXeY⋯H2O complexes (Y = Cl, Br, and I). J Chem Phys 2014; 140:044323. [DOI: 10.1063/1.4862692] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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9
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Liu X, Wang X, Xu B, Andrews L. Spectroscopic observation of photo-induced metastable linkage isomers of coinage metal (Cu, Ag, Au) sulfur dioxide complexes. Phys Chem Chem Phys 2014; 16:2607-20. [DOI: 10.1039/c3cp53811g] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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10
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Manna D, Ghosh A, Ghanty TK. Theoretical prediction of XRgCO(+) ions (X = F, Cl, and Rg = Ar, Kr, Xe). J Phys Chem A 2013; 117:14282-92. [PMID: 24295279 DOI: 10.1021/jp410631y] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
In this work we have predicted novel rare gas containing cationic molecules, XRgCO(+) (X = F, Cl and Rg = Ar, Kr, Xe) using ab initio quantum chemical methods. Detail structural, stability, vibrational frequency, and charge distribution values are reported using density functional theory, second-order Møller-Plesset perturbation theory, and coupled-cluster theory based methods. These ions are found to be metastable in nature and exhibit a linear geometry with C∞v symmetry in their minima energy structures, and the nonlinear transition state geometries are associated with Cs symmetry. Except for the two-body dissociation channel (Rg + XCO(+)), these ions are stable with respect to all other dissociation channels. However, the connecting transition states between the above-mentioned two-body dissociation channel products and the predicted ions are associated with sufficient energy barriers, which restricts the metastable species to transform into the global minimum products. Thus, it may be possible to detect and characterize these metastable ions using an electron bombardment technique under cryogenic conditions.
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Affiliation(s)
- Debashree Manna
- Theoretical Chemistry Section, Chemistry Group, Bhabha Atomic Research Centre , Mumbai 400 085, India
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11
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Tsuge M, Lignell A, Räsänen M, Khriachtchev L. Environmental effects on noble-gas hydrides: HXeBr, HXeCCH, and HXeH in noble-gas and molecular matrices. J Chem Phys 2013; 139:204303. [DOI: 10.1063/1.4832384] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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12
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Tsuge M, Berski S, Räsänen M, Latajka Z, Khriachtchev L. Experimental and computational study of the HXeI⋯HY complexes (Y = Br and I). J Chem Phys 2013; 138:104314. [DOI: 10.1063/1.4794309] [Citation(s) in RCA: 12] [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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13
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Tsuge M, Berski S, Stachowski R, Räsänen M, Latajka Z, Khriachtchev L. High Kinetic Stability of HXeBr upon Interaction with Carbon Dioxide: HXeBr···CO2 Complex in a Xenon Matrix and HXeBr in a Carbon Dioxide Matrix. J Phys Chem A 2012; 116:4510-7. [DOI: 10.1021/jp301704n] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Masashi Tsuge
- Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014, Finland
| | - Slawomir Berski
- Faculty of Chemistry, University of Wroclaw, 14, F. Joliot-Curie Str., 50-383
Wroclaw, Poland
| | - Radoslaw Stachowski
- Faculty of Chemistry, University of Wroclaw, 14, F. Joliot-Curie Str., 50-383
Wroclaw, Poland
- Wroclaw Centre
for Networking
and Supercomputing, HPC Department, Technical University, pl. Grunwaldzki 9, bud. D2/101, 50-337 Wroclaw, Poland
| | - Markku Räsänen
- Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014, Finland
| | - Zdzislaw Latajka
- Faculty of Chemistry, University of Wroclaw, 14, F. Joliot-Curie Str., 50-383
Wroclaw, Poland
| | - Leonid Khriachtchev
- Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014, Finland
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Paulson LO, Anderson DT, Lundell J, Marushkevich K, Melavuori M, Khriachtchev L. Conformation Resolved Induced Infrared Activity: trans- and cis-Formic Acid Isolated in Solid Molecular Hydrogen. J Phys Chem A 2011; 115:13346-55. [DOI: 10.1021/jp204600v] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Leif O. Paulson
- Department of Chemistry, University of Wyoming, Laramie, Wyoming 82071, United States
| | - David T. Anderson
- Department of Chemistry, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Jan Lundell
- Department of Chemistry, University of Jyväskylä, P.O. Box 35, FIN-40014 Jyväskylä, Finland
| | | | - Mia Melavuori
- Department of Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland
| | - Leonid Khriachtchev
- Department of Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland
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Khriachtchev L, Tapio S, Domanskaya AV, Räsänen M, Isokoski K, Lundell J. HXeOBr in a xenon matrix. J Chem Phys 2011; 134:124307. [DOI: 10.1063/1.3570826] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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16
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Khriachtchev L, Tapio S, Räsänen M, Domanskaya A, Lignell A. HY⋯N2 and HXeY⋯N2 complexes in solid xenon (Y=Cl and Br): Unexpected suppression of the complex formation for deposition at higher temperature. J Chem Phys 2010; 133:084309. [DOI: 10.1063/1.3472976] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [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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Pressure-induced bonding and compound formation in xenon-hydrogen solids. Nat Chem 2009; 2:50-3. [PMID: 21124380 DOI: 10.1038/nchem.445] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Accepted: 10/15/2009] [Indexed: 11/08/2022]
Abstract
Closed electron shell systems, such as hydrogen, nitrogen or group 18 elements, can form weakly bound stoichiometric compounds at high pressures. An understanding of the stability of these van der Waals compounds is lacking, as is information on the nature of their interatomic interactions. We describe the formation of a stable compound in the Xe-H(2) binary system, revealed by a suite of X-ray diffraction and optical spectroscopy measurements. At 4.8 GPa, a unique hydrogen-rich structure forms that can be viewed as a tripled solid hydrogen lattice modulated by layers of xenon, consisting of xenon dimers. Varying the applied pressure tunes the Xe-Xe distances in the solid over a broad range from that of an expanded xenon lattice to the distances observed in metallic xenon at megabar pressures. Infrared and Raman spectra indicate a weakening of the intramolecular covalent bond as well as persistence of semiconducting behaviour in the compound to at least 255 GPa.
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Corani A, Domanskaya A, Khriachtchev L, Räsänen M, Lignell A. Matrix-Isolation and Ab Initio Study of the HKrCl···HCl Complex. J Phys Chem A 2009; 113:10687-92. [PMID: 19757804 DOI: 10.1021/jp9044622] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Alice Corani
- Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland
| | - Alexandra Domanskaya
- Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland
| | - Leonid Khriachtchev
- Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland
| | - Markku Räsänen
- Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland
| | - Antti Lignell
- Laboratory of Physical Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland
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19
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Bochenkova AV, Bochenkov VE, Khriachtchev L. HArF in solid argon revisited: transition from unstable to stable configuration. J Phys Chem A 2009; 113:7654-9. [PMID: 19243121 DOI: 10.1021/jp810457h] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The thermal conversion of HArF configurations in solid argon has been investigated both experimentally and theoretically. The matrix isolation experiments have been concentrated on temperatures 25-27 K, promoting the transition from the unstable to stable HArF configuration. The combined quantum mechanical-molecular mechanical and temperature-accelerated dynamics approach has been developed to study the real-time evolution of HArF trapped in different matrix-site morphologies. Two realistic pathways of the stable HArF formation are found for annealing at 25-27 K. The conversion mechanism in both pathways involves the local mobility of matrix vacancies in the vicinity of the HArF molecule. These two relaxation processes occurring within different timescales can cause the multiexponential decay of unstable HArF observed experimentally. The theoretical values of the activation energy of 64 meV as well as the corresponding pre-exponential factor of exp(28) s(-1), obtained for one of the unstable HArF configurations, are well consistent with the experimental estimates of 70 meV and exp(30 +/- 3) s(-1), respectively.
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Affiliation(s)
- Anastasia V Bochenkova
- Department of Chemistry, M. V. Lomonosov Moscow State University, 1/3 Leninskie Gory, 119991 Moscow, Russian Federation.
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Khriachtchev L, Räsänen M, Gerber RB. Noble-gas hydrides: new chemistry at low temperatures. Acc Chem Res 2009; 42:183-91. [PMID: 18720951 DOI: 10.1021/ar800110q] [Citation(s) in RCA: 201] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Noble-gas chemistry has been undergoing a renaissance in recent years, due in large part to noble-gas hydrides, HNgY, where Ng = noble-gas atom and Y = electronegative fragment. These molecules are exceptional because of their relatively weak bonding and large dipole moments, which lead to strongly enhanced effects of the environment, complexation, and reactions. In this Account, we discuss the matrix-isolation synthesis of noble-gas hydrides, their spectroscopic and structural properties, and their stabilities.This family of species was discovered in 1995 and now has 23 members that are prepared in noble-gas matrices (HXeBr, HKrCl, HXeH, HXeOH, HXeO, etc.). The preparations of the first neutral argon molecule, HArF, and halogen-free organic noble-gas molecules (HXeCCH, HXeCC, HKrCCH, etc.) are important highlights of the field. These molecules are formed by the neutral H + Ng + Y channel. The first addition reaction involving HNgY molecules was HXeCC + Xe + H --> HXeCCXeH, and this led to the first hydride with two noble-gas atoms (recently extended by HXeOXeH). The experimental synthesis of HNgY molecules starts with production of H and Y fragments in solid noble gas via the UV photolysis of suitable precursors. The HNgY molecules mainly form upon thermal mobilization of the fragments.One of the unusual properties of these molecules is the hindered rotation of some HNgY molecules in solid matrices; this has been theoretically modeled. HNgY molecules also have unusual solvation effects, and the H-Xe stretching mode shifts to higher frequencies (up to about 150 cm-1) upon interaction with other species.The noble hydrides have a new bonding motif: HNgY molecules can be represented in the form (H-Ng)+Y-, where (H-Ng)+ is mainly covalent, whereas the interaction between (HNg)+ and Y- is predominantly ionic. The HNgY molecules are highly metastable species representing high-energy materials. The decomposition process HNgY --> Ng + HY is always strongly exoergic; however, the decomposition is prevented by high barriers, for instance, about 2 eV for HXeCCH. The other decomposition channel HNgY --> H + Ng + Y is endothermic for all prepared molecules.Areas that appear promising for further study include the extension of argon chemistry, preparation of new bonds with noble-gas atoms (such as Xe-Si bond), and studies of radon compounds. The calculations suggest the existence of related polymers, aggregates, and even HNgY crystals, and their experimental preparation is a major challenge. Another interesting task, still in its early stages, is the preparation of HNgY molecules in the gas phase.
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Affiliation(s)
- Leonid Khriachtchev
- Laboratory of Physical Chemistry, P.O. Box 55, University of Helsinki, FIN-00014, Finland,
| | - Markku Räsänen
- Laboratory of Physical Chemistry, P.O. Box 55, University of Helsinki, FIN-00014, Finland,
| | - R. Benny Gerber
- Department of Physical Chemistry, Hebrew University, Jerusalem 91904, Israel
- Department of Chemistry, University of California, Irvine, California 92697
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Lignell A, Khriachtchev L. Intermolecular interactions involving noble-gas hydrides: Where the blue shift of vibrational frequency is a normal effect. J Mol Struct 2008. [DOI: 10.1016/j.molstruc.2008.07.010] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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22
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Lignell A, Lundell J, Khriachtchev L, Räsänen M. Experimental and Computational Study of HXeY···HX Complexes (X, Y = Cl and Br): An Example of Exceptionally Large Complexation Effect. J Phys Chem A 2008; 112:5486-94. [DOI: 10.1021/jp801363u] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Antti Lignell
- Department of Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland, and Department of Chemistry, P.O. Box 35, FIN-40014 University of Jyväskylä, Finland
| | - Jan Lundell
- Department of Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland, and Department of Chemistry, P.O. Box 35, FIN-40014 University of Jyväskylä, Finland
| | - Leonid Khriachtchev
- Department of Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland, and Department of Chemistry, P.O. Box 35, FIN-40014 University of Jyväskylä, Finland
| | - Markku Räsänen
- Department of Chemistry, P.O. Box 55, FIN-00014 University of Helsinki, Finland, and Department of Chemistry, P.O. Box 35, FIN-40014 University of Jyväskylä, Finland
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Tanskanen H, Johansson S, Lignell A, Khriachtchev L, Räsänen M. Matrix isolation and ab initio study of the HXeCCH⋯CO2 complex. J Chem Phys 2007; 127:154313. [DOI: 10.1063/1.2780846] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Khriachtchev L, Lignell A, Tanskanen H, Lundell J, Kiljunen H, Räsänen M. Insertion of noble gas atoms into cyanoacetylene: an ab initio and matrix isolation study. J Phys Chem A 2007; 110:11876-85. [PMID: 17048820 DOI: 10.1021/jp063731f] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A computational and experimental matrix isolation study of insertion of noble gas atoms into cyanoacetylene (HCCCN) is presented. Twelve novel noble gas insertion compounds are found to be kinetically stable at the MP2 level of theory, including four molecules with argon. The first group of the computationally studied molecules belongs to noble gas hydrides (HNgCCCN and HNgCCNC), and we found their stability for Ng = Ar, Kr, and Xe. The HNgCCCN compounds with Kr and Xe have similar stability to that of previously reported HKrCN and HXeCN. The HArCCCN molecule seems to have a weaker H-Ar bond than in the previously identified HArF molecule. The HNgCCNC molecules are less stable than the HNgCCCN isomers for all noble gas atoms. The second group of the computational insertion compounds, HCCNgCN and HCCNgNC, are of a different type, and they also are kinetically stable for Ng = Ar, Kr, and Xe. Our photolysis and annealing experiments with low-temperature cyanoacetylene/Ng (Ng = Ar, Kr, and Xe) matrixes evidence the formation of two noble gas hydrides for Ng = Kr and Xe, with the strongest IR absorption bands at 1492.1 and 1624.5 cm(-1), and two additional absorption modes for each species are found. The computational spectra of HKrCCCN and HXeCCCN fit most closely the experimental data, which is the basis for our assignment. The obtained species absorb at quite similar frequencies as the known HKrCN and HXeCN molecules, which is in agreement with the theoretical predictions. No strong candidates for an Ar compound are observed in the IR absorption spectra. As an important side product of this work, the data obtained in long-term decay of KrHKr+ cations suggest a tentative assignment for the CCCN radical.
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Affiliation(s)
- Leonid Khriachtchev
- Department of Chemistry, and VERIFIN, PO Box 55, FIN-00014 University of Helsinki, Finland.
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Marushkevich K, Khriachtchev L, Räsänen M. High-energy conformer of formic acid in solid neon: Giant difference between the proton tunneling rates ofcismonomer andtrans-cisdimer. J Chem Phys 2007; 126:241102. [PMID: 17614528 DOI: 10.1063/1.2752152] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
We study the conformational reorganization of formic acid (FA) in solid neon and report the higher-energy cis-FA monomer and one form of the trans-cis FA dimers. They were prepared by selective vibrational excitation of the trans-FA monomer and trans-trans dimer. The proton tunneling decay of cis-FA monomer is surprisingly very fast in solid neon, two orders of magnitude faster than in solid argon. It was also found that the stability of the trans-cis dimer against proton tunneling is enormously enhanced in solid neon compared to the monomer (by a factor of approximately 300). These results are discussed in terms of matrix solvation and hydrogen bonding.
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Affiliation(s)
- Kseniya Marushkevich
- Laboratory of Physical Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki, Finland
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Tanskanen H, Khriachtchev L, Lundell J, Räsänen M. HXeCCH in Ar and Kr matrices. J Chem Phys 2006; 125:074501. [PMID: 16942345 DOI: 10.1063/1.2221308] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
HXeCCH molecule is prepared in Ar and Kr matrices and characterized by IR absorption spectroscopy. The experiments show that HXeCCH can be made in another host than the polarizable Xe environment. The H-Xe stretching absorption of HXeCCH in Ar and Kr is blueshifted from the value measured in solid Xe. The maximum blueshifts are +44.9 and +32.3 cm(-1) in Ar and Kr, respectively, indicating stabilization of the H-Xe bond. HXeCCH has a doublet H-Xe stretching absorption measured in Xe, Kr, and Ar matrices with a splitting of 5.7, 13, and 14 cm(-1), respectively. Ab initio calculations for the 1:1 HXeCCHcdots, three dots, centeredNg complexes (Ng = Ar, Kr, or Xe) are used to analyze the interaction of the hosts with the embedded molecule. These calculations support the matrix-site model where the band splitting observed experimentally is caused by specific interactions of the HXeCCH molecule with noble-gas atoms in certain local morphologies. However, the 1:1 complexation is unable to explain the observed blueshifts of the H-Xe stretching band in Ar and Kr matrices compared to a Xe matrix. More sophisticated computational approach is needed to account in detail the effects of solid environment.
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Affiliation(s)
- Hanna Tanskanen
- Department of Chemistry, University of Helsinki, P.O. Box 55, Helsinki FIN-00014, Finland.
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Kozlov MG, Derevianko A. Proposal for a sensitive search for the electric dipole moment of the electron with matrix-isolated radicals. PHYSICAL REVIEW LETTERS 2006; 97:063001. [PMID: 17026169 DOI: 10.1103/physrevlett.97.063001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2006] [Indexed: 05/12/2023]
Abstract
We propose using matrix-isolated paramagnetic diatomic molecules to search for the electric dipole moment of the electron (eEDM). As was suggested by Shapiro in 1968, the eEDM leads to a magnetization of a sample in the external electric field. In a typical condensed matter experiment, the effective field on the unpaired electron is of the same order of magnitude as the laboratory field, typically about 10(5) V/cm. We exploit the fact that the effective electric field inside heavy polar molecules is on the order of 10(10) V/cm. This leads to a huge enhancement of the Shapiro effect. Statistical sensitivity of the proposed experiment may allow one to improve the current limit on eEDM by 3 orders of magnitude in a few hours accumulation time.
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Affiliation(s)
- M G Kozlov
- Petersburg Nuclear Physics Institute, Gatchina 188300, Russia
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Ghanty TK. How strong is the interaction between a noble gas atom and a noble metal atom in the insertion compounds MNgF (M=Cu and Ag, and Ng=Ar, Kr, and Xe)? J Chem Phys 2006; 124:124304. [PMID: 16599671 DOI: 10.1063/1.2173991] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Ab initio molecular orbital calculations have been carried out to investigate the structure and the stability of noble gas insertion compounds of the type MNgF (M=Cu and Ag, and Ng=Ar, Kr, and Xe) through second order Moller-Plesset perturbation method. All the species are found to have a linear structure with a noble gas-noble metal bond, the distance of which is closer to the respective covalent bond length in comparison with the relevant van der Waals limit. The dissociation energies corresponding to the lowest energy fragmentation products, MF+Ng, have been found to be in the range of -231 to -398 kJ/mol. The respective barrier heights pertinent to the bent transition states (M-Ng-F bending mode) are quite high for the CuXeF and AgXeF species, although for the Ar and Kr containing species the same are rather low. Nevertheless the M-Ng bond length in MNgF compounds reported here is the smallest M-Ng bond ever predicted through any experimental or theoretical investigation, indicating strongest M-Ng interaction. All these species (except AgArF) are found to be metastable in their respective potential energy surface, and the dissociation energies corresponding to the M+Ng+F fragments have been calculated to be 30.1-155.3 kJ/mol. Indeed, in the present work we have demonstrated that the noble metal-noble gas interaction strength in MNgF species (with M=Cu and Ag, and Ng=Kr and Xe) is much stronger than that in NgMF systems. Bader's [Atoms in molecules-A Quantum Theory (Oxford University Press, Oxford, 1990)] topological theory of atoms in molecules (AIM) has been employed to explore the nature of interactions involved in these systems. Geometric as well as energetic considerations along with AIM results suggest a partial covalent nature of M-Ng bonds in these systems. The present results strengthen our earlier work and further support the proposition on the possibility of experimental identification of this new class of insertion compounds of noble gas atoms containing noble gas-noble metal bond.
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Affiliation(s)
- Tapan K Ghanty
- Theoretical Chemistry Section, Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400 085, India.
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Khriachtchev L, Lignell A, Räsänen M. Neutralization of solvated protons and formation of noble-gas hydride molecules: Matrix-isolation indications of tunneling mechanisms? J Chem Phys 2005; 123:64507. [PMID: 16122326 DOI: 10.1063/1.1953467] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The (NgHNg)+ cations (Ng = Ar and Kr) produced via the photolysis of HFAr, HFKr, and HBrKr solid mixtures are studied, with emphasis on their decay mechanisms. The present experiments provide a large variety of parameters connected to this decay phenomenon, which allows us to reconsider various models for the decay of the (NgHNg)+ cations in noble-gas matrices. As a result, we propose that this phenomenon could be explained by the neutralization of the solvated protons by electrons. The mechanism of this neutralization reaction probably involves tunneling of an electron from an electronegative fragment or another trap to the (NgHNg)+ cation. The proposed electron-tunneling mechanism should be considered as a possible alternative to the literature models based on tunneling-assisted or radiation-induced diffusion of protons in noble-gas solids. As a novel experimental observation of this work, the efficient formation of HArF molecules occurs at 8 K in a photolyzed HFAr matrix. It is probable that the low-temperature formation of HArF involves local tunneling of the H atom to the Ar-F center, which in turn supports the locality of HF photolysis in solid Ar. In this model, the decay of (ArHAr)+ ions and the formation of HArF molecules observed at low temperatures are generally unconnected processes; however, the decaying (ArHAr)+ ions may contribute to some extent to the formation of HArF molecules.
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Affiliation(s)
- Leonid Khriachtchev
- Laboratory of Physical Chemistry, P.O. Box 55, University of Helsinki, Helsinki FIN-00014, Finland.
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Lignell A, Khriachtchev L, Mustalampi H, Nurminen T, Räsänen M. Interaction of bihalogen anions with nitrogen: Matrix-isolation study and first principle calculations of the (ClHCl)−⋯N2 and (BrHBr)−⋯N2 complexes. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.02.080] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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