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Wu H, Song Y, Zeng Y, Zhu G, Yu G, Yang Y. Femtosecond coherent anti-Stokes Raman spectroscopy study of vibrational dynamics of liquid chloroform. RSC Adv 2022; 12:27596-27603. [PMID: 36276055 PMCID: PMC9516355 DOI: 10.1039/d2ra04542g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 09/07/2022] [Indexed: 11/22/2022] Open
Abstract
Femtosecond time-resolved coherent anti-Stokes Raman spectroscopy (CARS) was used to study the dynamics of the vibrational modes of liquid chloroform. The vibrational modes were selectively excited and their coherent vibrational dynamics were obtained. Some subtle features that are difficult to distinguish in the ordinary spontaneous Raman spectrum, such as overtones and combinations of some fundamental vibrational modes, were recognized from the CARS transients. Combined with theoretical calculations, the contributions of chlorine isotopes were also confirmed from the CARS transients of the vibrational modes involving the motion of chlorine atoms.
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Affiliation(s)
- Honglin Wu
- National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics Mianyang China
| | - Yunfei Song
- National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics Mianyang China
| | - YangYang Zeng
- National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics Mianyang China
| | - Gangbei Zhu
- National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics Mianyang China
| | - Guoyang Yu
- National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics Mianyang China
| | - Yanqiang Yang
- National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics Mianyang China
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2
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Blancafort-Jorquera M, González M. Vibrational energy relaxation of a diatomic molecule in a superfluid helium nanodroplet: influence of the nanodroplet size, interaction energy and energy gap. Phys Chem Chem Phys 2021; 23:25961-25973. [PMID: 34783338 DOI: 10.1039/d1cp03629g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The influence of the nanodroplet size, molecule-helium interaction potential energy and ν = 1 - ν = 0 vibrational energy gap on the vibrational energy relaxation (VER) of a diatomic molecule (X2) in a superfluid helium nanodroplet [HeND or (4He)N; finite quantum solvent at T = 0.37 K] has been studied using a hybrid quantum approach recently proposed by us and taking as a reference the VER results on the I2@(4He)100 doped nanodroplet (Vilà et al., Phys. Chem. Chem. Phys., 2018, 20, 118, which corresponds to the first theoretical study on the VER of molecules embedded in a HeND). This has allowed us to obtain a deeper insight into the vibrational relaxation dynamics. The nanodroplet size has a very small effect on the VER, as this process mainly depends on the interaction between the molecule and the nanodroplet first solvation shell. Regarding the interaction potential energy and the energy gap, both factors play an important and comparable role in the VER time properties (global relaxation time, lifetime and transition time). As the former becomes stronger the relaxation time properties decrease in a significant way (their inverse follows a linear dependence with respect to the ν = 1 - ν = 0 coupling term) and they also decrease in a significant manner when the energy gap diminishes (linear dependence on the ν = 1 - ν = 0 energy difference). We expect that this study will motivate further work on the vibrational relaxation process in HeNDs.
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Affiliation(s)
- Miquel Blancafort-Jorquera
- Departament de Ciència dels Materials i Química Física and IQTC, Universitat de Barcelona, Martí i Franquès, 1-11, 08028 Barcelona, Spain.
| | - Miguel González
- Departament de Ciència dels Materials i Química Física and IQTC, Universitat de Barcelona, Martí i Franquès, 1-11, 08028 Barcelona, Spain.
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3
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Buchholz M, Grossmann F, Ceotto M. Simplified approach to the mixed time-averaging semiclassical initial value representation for the calculation of dense vibrational spectra. J Chem Phys 2018; 148:114107. [DOI: 10.1063/1.5020144] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Max Buchholz
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
| | - Frank Grossmann
- Institut für Theoretische Physik, Technische Universität Dresden, 01062 Dresden, Germany
| | - Michele Ceotto
- Dipartimento di Chimica, Università degli Studi di Milano, Via C. Golgi 19, 20133 Milano, Italy
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4
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Vilà A, Paniagua M, González M. Vibrational energy relaxation dynamics of diatomic molecules inside superfluid helium nanodroplets. The case of the I2 molecule. Phys Chem Chem Phys 2018; 20:118-130. [DOI: 10.1039/c7cp05694j] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The vibrational relaxation (VER) of a X2 molecule in a 4He superfluid nanodroplet (HeND; 0.37 K) was studied adapting a quantum approach recently proposed by us. In the first theoretical study on the VER of molecules inside HeND the I2 molecule was examined [cascade mechanism (ν → ν − 1; ν − 1 → ν − 2; …) and time scale of ns].
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Affiliation(s)
- Arnau Vilà
- Departament de Ciència de Materials i Química Física and IQTC
- Universitat de Barcelona
- 08028 Barcelona
- Spain
- Departamento de Química Física Aplicada
| | - Miguel Paniagua
- Departamento de Química Física Aplicada
- Universidad Autónoma de Madrid
- 28049 Cantoblanco
- Spain
| | - Miguel González
- Departament de Ciència de Materials i Química Física and IQTC
- Universitat de Barcelona
- 08028 Barcelona
- Spain
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5
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Kovac PA, Cina JA. Mixed quantum/semiclassical wave-packet dynamical method for condensed-phase molecular spectroscopy signals. J Chem Phys 2017; 147:224112. [DOI: 10.1063/1.5003386] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Philip A. Kovac
- Department of Chemistry and Biochemistry, and Oregon Center for Optical, Molecular, and Quantum Science, University of Oregon, Eugene, Oregon 97403, USA
| | - Jeffrey A. Cina
- Department of Chemistry and Biochemistry, and Oregon Center for Optical, Molecular, and Quantum Science, University of Oregon, Eugene, Oregon 97403, USA
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6
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Park KD, Muller EA, Kravtsov V, Sass PM, Dreyer J, Atkin JM, Raschke MB. Variable-Temperature Tip-Enhanced Raman Spectroscopy of Single-Molecule Fluctuations and Dynamics. NANO LETTERS 2016; 16:479-87. [PMID: 26679007 DOI: 10.1021/acs.nanolett.5b04135] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Structure, dynamics, and coupling involving single-molecules determine function in catalytic, electronic or biological systems. While vibrational spectroscopy provides insight into molecular structure, rapid fluctuations blur the molecular trajectory even in single-molecule spectroscopy, analogous to spatial averaging in measuring large ensembles. To gain insight into intramolecular coupling, substrate coupling, and dynamic processes, we use tip-enhanced Raman spectroscopy (TERS) at variable and cryogenic temperatures, to slow and control the motion of a single molecule. We resolve intrinsic line widths of individual normal modes, allowing detailed and quantitative investigation of the vibrational modes. From temperature dependent line narrowing and splitting, we quantify ultrafast vibrational dephasing, intramolecular coupling, and conformational heterogeneity. Through statistical correlation analysis of fluctuations of individual modes, we observe rotational motion and spectral fluctuations of the molecule. This work demonstrates single-molecule vibrational spectroscopy beyond chemical identification, opening the possibility for a complete picture of molecular motion ranging from femtoseconds to minutes.
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Affiliation(s)
- Kyoung-Duck Park
- Department of Physics, Department of Chemistry, and JILA, University of Colorado , Boulder, Colorado 80309, United States
| | - Eric A Muller
- Department of Physics, Department of Chemistry, and JILA, University of Colorado , Boulder, Colorado 80309, United States
| | - Vasily Kravtsov
- Department of Physics, Department of Chemistry, and JILA, University of Colorado , Boulder, Colorado 80309, United States
| | - Paul M Sass
- Department of Physics, Department of Chemistry, and JILA, University of Colorado , Boulder, Colorado 80309, United States
| | - Jens Dreyer
- German Research School for Simulation Sciences, RWTH Aachen University and Forschungszentrum Jülich , D-52425 Jülich, Germany
| | - Joanna M Atkin
- Department of Physics, Department of Chemistry, and JILA, University of Colorado , Boulder, Colorado 80309, United States
- Department of Chemistry, University of North Carolina , Chapel Hill, North Carolina 27599, United States
| | - Markus B Raschke
- Department of Physics, Department of Chemistry, and JILA, University of Colorado , Boulder, Colorado 80309, United States
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7
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Cheng X, Cina JA. Variational mixed quantum/semiclassical simulation of dihalogen guest and rare-gas solid host dynamics. J Chem Phys 2014; 141:034113. [DOI: 10.1063/1.4887457] [Citation(s) in RCA: 9] [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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8
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Lindgren J, Hulkko E, Kiviniemi T, Pettersson M, Apkarian VA, Kiljunen T. Dynamics Behind the Long-Lived Coherences of I2 in Solid Xe. J Phys Chem A 2013; 117:4884-97. [DOI: 10.1021/jp402732b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Johan Lindgren
- Nanoscience Center, Department
of Chemistry, P. O. Box 35, FI-40014 University of Jyväskylä, Finland
| | - Eero Hulkko
- Nanoscience Center, Department
of Chemistry, P. O. Box 35, FI-40014 University of Jyväskylä, Finland
- Department of
Chemistry, University of California, Irvine,
California 92697-2025,
United States
| | - Tiina Kiviniemi
- Nanoscience Center, Department
of Chemistry, P. O. Box 35, FI-40014 University of Jyväskylä, Finland
| | - Mika Pettersson
- Nanoscience Center, Department
of Chemistry, P. O. Box 35, FI-40014 University of Jyväskylä, Finland
| | - V. Ara Apkarian
- Department of
Chemistry, University of California, Irvine,
California 92697-2025,
United States
| | - Toni Kiljunen
- Nanoscience Center, Department
of Chemistry, P. O. Box 35, FI-40014 University of Jyväskylä, Finland
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9
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Buchholz M, Goletz CM, Grossmann F, Schmidt B, Heyda J, Jungwirth P. Semiclassical Hybrid Approach to Condensed Phase Molecular Dynamics: Application to the I2Kr17 Cluster. J Phys Chem A 2012; 116:11199-210. [DOI: 10.1021/jp305084f] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Max Buchholz
- Institut für Theoretische
Physik, Technische Universität Dresden, 01062 Dresden, Germany
| | | | - Frank Grossmann
- Institut für Theoretische
Physik, Technische Universität Dresden, 01062 Dresden, Germany
| | - Burkhard Schmidt
- Institut für Mathematik, Freie Universität Berlin, Arnimallee 6, 14195 Berlin, Germany
| | - Jan Heyda
- Institute for Soft Matter and Functional
Materials, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin,
Germany
| | - Pavel Jungwirth
- Institute of Organic
Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo nam. 2, 16610 Prague 6, Czech
Republic
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10
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Hulkko E, Ahokas J, Lindgren J, Myllyperkiö P, Pettersson M. Electronic spectroscopy of I(2)-Xe complexes in solid Krypton. J Chem Phys 2012; 136:174501. [PMID: 22583243 DOI: 10.1063/1.4706521] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In the present work, we have studied ion-pair states of matrix-isolated I(2) with vacuum-UV absorption and UV-vis-NIR emission, where the matrix environment is systematically changed by mixing Kr with Xe, from pure Kr to a more polarizable Xe host. Particular emphasis is put on low doping levels of Xe that yield a binary complex I(2)-Xe, as verified by coherent anti-Stokes Raman scattering (CARS) measurements. Associated with interaction of I(2) with Xe we can observe strong new absorption in vacuum-UV, redshifted 2400 cm(-1) from the X → D transition of I(2). Observed redshift can be explained by symmetry breaking of ion-pair states within the I(2)-Xe complex. Systematic Xe doping of Kr matrices shows that at low doping levels, positions of I(2) ion-pair emissions are not significantly affected by complexation with Xe, but simultaneous increase of emissions from doubly spin-excited states indicates non-radiative relaxation to valence states. At intermediate doping levels ion-pair emissions shift systematically to red due to change in the average polarizability of the environment. We have conducted spectrally resolved ultrafast pump-probe ion-pair emission studies with pure and Xe doped Kr matrices, in order to reveal the influence of Xe to I(2) dynamics in solid Kr. Strikingly, relaxed emission from the ion-pair states shows no indication of complex presence. It further indicates that the complex escapes detection due to a non-radiative relaxation.
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Affiliation(s)
- Eero Hulkko
- Nanoscience Center, Department of Chemistry, University of Jyväskylä, P.O. Box 35, FIN-40014, Finland.
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11
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Lindgren J, Hulkko E, Pettersson M, Kiljunen T. Rotational coherence imaging and control for CN molecules through time-frequency resolved coherent anti-Stokes Raman scattering. J Chem Phys 2011; 135:224514. [PMID: 22168710 DOI: 10.1063/1.3665934] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Numerical wave packet simulations are performed for studying coherent anti-Stokes Raman scattering (CARS) for CN radicals. Electronic coherence is created by femtosecond laser pulses between the X(2)Σ and B(2)Σ states. Due to the large energy separation of vibrational states, the wave packets are superpositions of rotational states only. This allows for a specially detailed inspection of the second- and third-order coherences by a two-dimensional imaging approach. We present the time-frequency domain images to illustrate the intra- and intermolecular interferences, and discuss the procedure to rationally control and experimentally detect the interferograms in solid Xe environment.
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Affiliation(s)
- Johan Lindgren
- Department of Chemistry, Nanoscience Center, P.O. Box 35, FI-40014 University of Jyväskylä, Finland
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12
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Simulation of vibrational dephasing in liquid water using the semiclassical Liouville method. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.05.046] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Chapman CT, Cheng X, Cina JA. Numerical Tests of a Fixed Vibrational Basis/Gaussian Bath Theory for Small Molecule Dynamics in Low-Temperature Media. J Phys Chem A 2011; 115:3980-9. [DOI: 10.1021/jp108921x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Craig T. Chapman
- Departments of †Chemistry and ‡Physics and Oregon Center for Optics, University of Oregon, Eugene, Oregon 97403, United States
| | - Xiaolu Cheng
- Departments of †Chemistry and ‡Physics and Oregon Center for Optics, University of Oregon, Eugene, Oregon 97403, United States
| | - Jeffrey A. Cina
- Departments of †Chemistry and ‡Physics and Oregon Center for Optics, University of Oregon, Eugene, Oregon 97403, United States
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14
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Grüner B, Schlesinger M, Heister P, Strunz WT, Stienkemeier F, Mudrich M. Vibrational relaxation and dephasing of Rb2 attached to helium nanodroplets. Phys Chem Chem Phys 2011; 13:6816-26. [PMID: 21394372 DOI: 10.1039/c0cp02355h] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The vibrational wave-packet dynamics of diatomic rubidium molecules (Rb(2)) in triplet states formed on the surface of superfluid helium nanodroplets is investigated both experimentally and theoretically. Detailed comparison of experimental femtosecond pump-probe spectra with dissipative quantum dynamics simulations reveals that vibrational relaxation is the main source of dephasing. The rate constant for vibrational relaxation in the first excited triplet state 1(3)Σ(g)+ is found to be constant γ ≈ 0.5 ns(-1) for the lowest vibrational levels v ≲ 15 and to increase sharply when exciting to higher energies.
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Affiliation(s)
- B Grüner
- Physikalisches Institut, Universität Freiburg, 79104 Freiburg, Germany
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15
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Branigan ET, van Staveren MN, Apkarian VA. Solidlike coherent vibronic dynamics in a room temperature liquid: Resonant Raman and absorption spectroscopy of liquid bromine. J Chem Phys 2010; 132:044503. [DOI: 10.1063/1.3291610] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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16
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Hulkko E, Kiljunen T, Kiviniemi T, Pettersson M. From monomer to bulk: appearance of the structural motif of solid iodine in small clusters. J Am Chem Soc 2009; 131:1050-6. [PMID: 19123809 DOI: 10.1021/ja806537u] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Formation of iodine clusters in a solid krypton matrix was studied using resonance Raman spectroscopy with a 1 cm(-1) resolution. The clusters were produced by annealing of the solid and recognized by appearance of additional spectral transitions. Two distinct regions, red-shifted from the fundamental vibrational wavenumber of the isolated I(2) at 211 cm(-1), were observed in the signal. The intermediate region spans the range 196-208 cm(-1), and the ultimate region consists of two peaks at 181 and 190 cm(-1) nearly identical to crystalline I(2). The experimental results were compared to DFT-D level electronic structure calculations of planar (I(2))(n) clusters (n = 1-7). The dimer, trimer, and tetramer structures, where the I(2) molecule is complexed from one end, were found to exhibit vibrational shifts corresponding to the intermediate size clusters. The larger, bulklike shift appears when the iodine molecule is coordinated from two opposite directions as in the case of a pentamer and higher clusters. Starting from the pentamer, the structural motif of crystalline iodine is clearly recognized in the clusters.
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Affiliation(s)
- Eero Hulkko
- Nanoscience Center, Department of Chemistry, P.O. Box 35, FI-40014 University of Jyvaskyla, Finland
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17
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Ma Z, Coker DF. Quantum initial condition sampling for linearized density matrix dynamics: Vibrational pure dephasing of iodine in krypton matrices. J Chem Phys 2008; 128:244108. [DOI: 10.1063/1.2944270] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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18
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Cina JA. Wave-Packet Interferometry and Molecular State Reconstruction: Spectroscopic Adventures on the Left-Hand Side of the Schrödinger Equation. Annu Rev Phys Chem 2008; 59:319-42. [DOI: 10.1146/annurev.physchem.59.032607.093753] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Jeffrey A. Cina
- Department of Chemistry and Oregon Center for Optics, University of Oregon, Eugene, Oregon 97403;
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19
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Ibrahim H, Gühr M, Schwentner N. Valence transitions of Br2 in Ar matrices: interaction with the lattice and predissociation. J Chem Phys 2008; 128:064504. [PMID: 18282053 DOI: 10.1063/1.2826341] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Fluorescence spectra from v(')=0 of the B, A and A(') states of Br(2)Ar are presented for excitation wavelengths from 630 to 540 nm with high resolution, to evaluate isotopic splittings in emission and absorption. The observed progression of sharp zero phonon lines (ZPLs) from v(')=2 to v(')=19 in B excitation is used to derive spectroscopic constants. The ZPL broadening and the growing phonon sideband (PSB) contributions indicate an increase of matrix influence on the X-B transition with rising v('). Contributions of the PSB are parameterized with the Huang-Rhys coupling constant S, where S=1 near the potential minimum reflects the electron-phonon coupling and S=4 close to Franck-Condon maximum originates from vibrational coupling. The PSB spectral composition correlates with the matrix phonon density of states, and the ZPL broadens and shifts with temperature. Two crossings with repulsive states (between v(')=4-5 and v(')=7-9) leading to matrix induced predissociation and a third tentative one between v(')=14 and 15 are indicated by ZPL broadening, population flow, and spectral shifts. The crossing energies are close to gas phase and matrix calculations. The stepwise flow of intensity from B via repulsive states to A(') and, similarly, from the A continuum to A(') is discussed. Emission quantum efficiency of the B state decreases from near unity at v(')=0 to less than 10(-3) at v(')=19. Broadening of ZPL near crossings yields predissociation times of 5 and 2.5 ps corresponding to probabilities of 5% and 10% per round-trip for the two lowest crossings, respectively.
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Affiliation(s)
- Heide Ibrahim
- Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany.
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20
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Gühr M, Bargheer M, Fushitani M, Kiljunen T, Schwentner N. Ultrafast dynamics of halogens in rare gas solids. Phys Chem Chem Phys 2007; 9:779-801. [PMID: 17287873 DOI: 10.1039/b609058n] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We perform time resolved pump-probe spectroscopy on small halogen molecules ClF, Cl2, Br2, and I2 embedded in rare gas solids (RGS). We find that dissociation, angular depolarization, and the decoherence of the molecule is strongly influenced by the cage structure. The well ordered crystalline environment facilitates the modelling of the experimental angular distribution of the molecular axis after the collision with the rare gas cage. The observation of many subsequent vibrational wave packet oscillations allows the construction of anharmonic potentials and indicate a long vibrational coherence time. We control the vibrational wave packet revivals, thereby gaining information about the vibrational decoherence. The coherence times are remarkable larger when compared to the liquid or high pressure gas phase. This fact is attributed to the highly symmetric molecular environment of the RGS. The decoherence and energy relaxation data agree well with a perturbative model for moderate vibrational excitation and follow a classical model in the strong excitation limit. Furthermore, a wave packet interferometry scheme is applied to deduce electronic coherence times. The positions of those cage atoms, excited by the molecular electronic transitions are modulated by long living coherent phonons of the RGS, which we can probe via the molecular charge transfer states.
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Affiliation(s)
- M Gühr
- Institut für Experimentalphysik, Freie Universität Berlin, Arnimallee 14, D-14195, Berlin, Germany
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21
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Kiviniemi T, Kiljunen T, Pettersson M. Femtosecond coherent anti-Stokes Raman-scattering polarization beat spectroscopy of I2–Xe complex in solid krypton. J Chem Phys 2006; 125:164302. [PMID: 17092068 DOI: 10.1063/1.2358987] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Time-resolved coherent anti-Stokes Raman-scattering (CARS) measurements are carried out to study the interaction between xenon atom and iodine molecule in a solid krypton matrix. Interference between the CARS polarizations of the "free" and complexed iodine molecules is observed, while the quantum beats of the complex are not detected due to low concentration. Vibrational analysis based on the polarization beats yields accurate molecular constants for the I2-Xe complex. The harmonic frequency of the I2-Xe complex is found to be redshifted by 0.90 cm-1 when compared to the free I2, whereas the anharmonicity is approximately the same. The dephasing rate of the complex is found to be somewhat higher than that of the free iodine molecule in solid Kr, showing that the complexation affects dephasing, although not dramatically. Molecular dynamics simulations are carried out to find the conformation of the complex, and wave packet simulations are used to reproduce the CARS signal to confirm the assignments of the observed beatings as quantum and polarization beats. The results show that the polarization beats are a useful tool for investigating weak interactions in condensed phase.
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Affiliation(s)
- Tiina Kiviniemi
- Nanoscience Center, Department of Chemistry, P.O. Box 35, FIN-40014 University of Jyväskylä, Finland
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22
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Riga JM, Fredj E, Martens CC. Simulation of vibrational dephasing of I2 in solid Kr using the semiclassical Liouville method. J Chem Phys 2006; 124:64506. [PMID: 16483219 DOI: 10.1063/1.2162878] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
In this paper, we present simulations of the decay of quantum coherence between vibrational states of I(2) in its ground (X) electronic state embedded in a cryogenic Kr matrix. We employ a numerical method based on the semiclassical limit of the quantum Liouville equation, which allows the simulation of the evolution and decay of quantum vibrational coherence using classical trajectories and ensemble averaging. The vibrational level-dependent interaction of the I(2)(X) oscillator with the rare-gas environment is modeled using a recently developed method for constructing state-dependent many-body potentials for quantum vibrations in a many-body classical environment [J. M. Riga, E. Fredj, and C. C. Martens, J. Chem. Phys. 122, 174107 (2005)]. The vibrational dephasing rates gamma(0n) for coherences prepared between the ground vibrational state mid R:0 and excited vibrational state mid R:n are calculated as a function of n and lattice temperature T. Excellent agreement with recent experiments performed by Karavitis et al. [Phys. Chem. Chem. Phys. 7, 791 (2005)] is obtained.
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Affiliation(s)
- Jeanne M Riga
- Department of Chemistry, University of California, Irvine, 92697-2025, USA
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Kiviniemi T, Aumanen J, Myllyperkiö P, Apkarian VA, Pettersson M. Time-resolved coherent anti-Stokes Raman-scattering measurements of I2 in solid Kr: Vibrational dephasing on the ground electronic state at 2.6–32 K. J Chem Phys 2005; 123:64509. [PMID: 16122328 DOI: 10.1063/1.1990115] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Time-resolved coherent anti-Stokes Raman-scattering (CARS) measurements are carried out for iodine (I2) in solid krypton matrices. The dependence of vibrational dephasing time on temperature and vibrational quantum number v is studied. The v dependence is approximately quadratic, while the temperature dependence of both vibrational dephasing and spectral shift, although weak, fits the exponential form characteristic of dephasing by pseudolocal phonons. The analysis of the data indicates that the frequency of the pseudolocal phonons is approximately 30 cm(-1). The longest dephasing times are observed for v = 2 being approximately 300 ps and limited by inhomogeneous broadening. An increase in the dephasing rate of v = 2 as the temperature is lowered to T = 2.6 K is taken as a clear indication of lattice-strain-induced inhomogeneity of the ensemble coherence.
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Affiliation(s)
- Tiina Kiviniemi
- Department of Chemistry, P.O. Box 35, FIN-40014 University of Jyväskylä, Finland
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