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Thon R, Chin W, Chamma D, Jonusas M, Galaup JP, Crépin C. Vibrational dynamics of iron pentacarbonyl in cryogenic matrices. J Chem Phys 2022; 156:024301. [PMID: 35032984 DOI: 10.1063/5.0073080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Iron pentacarbonyl is a textbook example of fluxionality. We trap the molecule in cryogenic matrices to study the vibrational dynamics of CO stretching modes involved in the fluxional rearrangement. The infrared spectrum in Ar and N2 is composed of about ten narrow bands in the spectral range of interest, indicating the population of various lattice sites and a lowering of the molecular symmetry in the trapping sites. The vibrational dynamics is explored by means of infrared stimulated photon echoes at the femtosecond scale. Vibrational dephasing and population relaxation times are obtained. The non-linear signals exhibit strong oscillations useful to disentangle the site composition of the absorption spectrum. The population relaxation involves at least two characteristic times. An evolution of the photon echo signals with the waiting time is observed. The behavior of all the signals can be reproduced within a simple model that describes the population relaxation occurring in two steps: relaxation of v = 1 (population time T1 < 100 ps) and return to v = 0 (recovery time > 1 ns). These two steps explain the evolution of the oscillations with the waiting time in the photon echo signals. These results discard fluxional rearrangement on the time scale of hundreds of ps in our samples. Dephasing times are of the same order of magnitude as T1: dephasing processes due to the matrix environment are rather inefficient. The photon echo experiments also reveal that intermolecular resonant vibrational energy transfers between guest molecules occur at the hundreds of ps time scale in concentrated samples (guest/host > 104).
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Affiliation(s)
- Raphaël Thon
- Institut des Sciences Moléculaires d'Orsay, UMR8214, CNRS-Université Paris-Saclay, F-91405 Orsay, France
| | - Wutharath Chin
- Institut des Sciences Moléculaires d'Orsay, UMR8214, CNRS-Université Paris-Saclay, F-91405 Orsay, France
| | - Didier Chamma
- Institut des Sciences Moléculaires d'Orsay, UMR8214, CNRS-Université Paris-Saclay, F-91405 Orsay, France
| | - Mindaugas Jonusas
- Institut des Sciences Moléculaires d'Orsay, UMR8214, CNRS-Université Paris-Saclay, F-91405 Orsay, France
| | - Jean-Pierre Galaup
- Institut des Sciences Moléculaires d'Orsay, UMR8214, CNRS-Université Paris-Saclay, F-91405 Orsay, France
| | - Claudine Crépin
- Institut des Sciences Moléculaires d'Orsay, UMR8214, CNRS-Université Paris-Saclay, F-91405 Orsay, France
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Dhont G, Fontanari D, Bray C, Mouret G, Cuisset A, Hindle F, Hickson KM, Bocquet R. Characterization of the Observed Electric Field and Molecular Relaxation Times for Millimeter-Wave Chirped Pulse Instrumentation. JOURNAL OF INFRARED, MILLIMETER AND TERAHERTZ WAVES 2020; 41:1009-1021. [PMID: 32837589 PMCID: PMC7327489 DOI: 10.1007/s10762-020-00716-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 06/01/2020] [Indexed: 06/11/2023]
Abstract
In a chirped pulse experiment, the strength of the signal level is proportional to the amplitude of the electric field, which is weaker in the millimeter-wave or submillimeter-wave region than in the microwave region. Experiments in the millimeter region thus require an optimization of the coupling between the source and the molecular system and a method to estimate the amplitude of the electric field as seen by the molecular system. We have developed an analytical model capable of reproducing the coherent transient signals obtained with a millimeter-wave chirped pulse setup operated in a monochromatic pulse mode. The fit of the model against the experimental data allowed access to the amplitude of the electric field and, as a byproduct, to the molecular relaxation times T 1 and T 2.
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Affiliation(s)
- G. Dhont
- LPCA, Université du Littoral Côte d’Opale, 189A avenue Maurice Schumann, 59140 Dunkerque, France
| | - D. Fontanari
- LPCA, Université du Littoral Côte d’Opale, 189A avenue Maurice Schumann, 59140 Dunkerque, France
| | - C. Bray
- LPCA, Université du Littoral Côte d’Opale, 189A avenue Maurice Schumann, 59140 Dunkerque, France
| | - G. Mouret
- LPCA, Université du Littoral Côte d’Opale, 189A avenue Maurice Schumann, 59140 Dunkerque, France
| | - A. Cuisset
- LPCA, Université du Littoral Côte d’Opale, 189A avenue Maurice Schumann, 59140 Dunkerque, France
| | - F. Hindle
- LPCA, Université du Littoral Côte d’Opale, 189A avenue Maurice Schumann, 59140 Dunkerque, France
| | - K. M. Hickson
- ISM, Université de Bordeaux, 351 cours de la libération, 33405 Talence cedex, France
| | - R. Bocquet
- LPCA, Université du Littoral Côte d’Opale, 189A avenue Maurice Schumann, 59140 Dunkerque, France
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Mendes M, Regeta K, Ferreira da Silva F, Jones NC, Hoffmann SV, García G, Daniel C, Limão-Vieira P. Comprehensive investigation of the electronic excitation of W(CO) 6 by photoabsorption and theoretical analysis in the energy region from 3.9 to 10.8 eV. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2017; 8:2208-2218. [PMID: 29114447 PMCID: PMC5669226 DOI: 10.3762/bjnano.8.220] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 09/29/2017] [Indexed: 06/07/2023]
Abstract
High-resolution vacuum ultraviolet photoabsorption measurements in the wavelength range of 115-320 nm (10.8-3.9 eV) have been performed together with comprehensive relativistic time-dependent density functional calculations (TDDFT) on the low-lying excited sates of tungsten hexacarbonyl, W(CO)6. The higher resolution obtained reveals previously unresolved spectral features of W(CO)6. The spectrum shows two higher-energy bands (in the energy ranges of 7.22-8.12 eV and 8.15-9.05 eV), one of them with clear vibrational structure, and a few lower-energy shoulders in addition to a couple of lower-energy metal-to-ligand charge-transfer (MLCT) bands reported in the literature before. Absolute photoabsorption cross sections are reported and, where possible, compared to previously published results. On the basis of this combined experimental/theoretical study the absorption spectrum of the complex has been totally re-assigned between 3.9 and 10.8 eV under the light of spin-orbit coupling (SOC) effects. The present comprehensive knowledge of the nature of the electronically excited states may be of relevance to estimate neutral dissociation cross sections of W(CO)6, a precursor molecule in focused electron beam induced deposition (FEBID) processes, from electron scattering measurements.
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Affiliation(s)
- Mónica Mendes
- Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal
| | - Khrystyna Regeta
- Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal
| | - Filipe Ferreira da Silva
- Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal
| | - Nykola C Jones
- ISA, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000, Aarhus C, Denmark
| | - Søren Vrønning Hoffmann
- ISA, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000, Aarhus C, Denmark
| | - Gustavo García
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas (CSIC), Serrano 113-bis, 28006 Madrid, Spain
| | - Chantal Daniel
- Laboratoire de Chimie Quantique, Institut de Chimie Strasbourg, UMR7177 CNRS/Université de Strasbourg 1 Rue Blaise Pascal BP296/R8, F-67008 Strasbourg, France
| | - Paulo Limão-Vieira
- Laboratório de Colisões Atómicas e Moleculares, CEFITEC, Departamento de Física, Universidade NOVA de Lisboa, 2829-516, Caparica, Portugal
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Thon R, Chin W, Chamma D, Galaup JP, Ouvrard A, Bourguignon B, Crépin C. Vibrational spectroscopy and dynamics of W(CO)6 in solid methane as a probe of lattice properties. J Chem Phys 2016; 145:214306. [DOI: 10.1063/1.4968561] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Affiliation(s)
- Raphael Thon
- Institut des Sciences Moléculaires d’Orsay (ISMO) UMR 8214, CNRS, Univ. Paris-Sud, Université Paris-Saclay, F-91405 Orsay, France
| | - Wutharath Chin
- Institut des Sciences Moléculaires d’Orsay (ISMO) UMR 8214, CNRS, Univ. Paris-Sud, Université Paris-Saclay, F-91405 Orsay, France
| | - Didier Chamma
- Institut des Sciences Moléculaires d’Orsay (ISMO) UMR 8214, CNRS, Univ. Paris-Sud, Université Paris-Saclay, F-91405 Orsay, France
| | - Jean-Pierre Galaup
- Laboratoire Aimé Cotton UMR 9188, CNRS, Univ. Paris Sud, Université Paris-Saclay, F-91405 Orsay, France
| | - Aimeric Ouvrard
- Institut des Sciences Moléculaires d’Orsay (ISMO) UMR 8214, CNRS, Univ. Paris-Sud, Université Paris-Saclay, F-91405 Orsay, France
| | - Bernard Bourguignon
- Institut des Sciences Moléculaires d’Orsay (ISMO) UMR 8214, CNRS, Univ. Paris-Sud, Université Paris-Saclay, F-91405 Orsay, France
| | - Claudine Crépin
- Institut des Sciences Moléculaires d’Orsay (ISMO) UMR 8214, CNRS, Univ. Paris-Sud, Université Paris-Saclay, F-91405 Orsay, France
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Nandi DK, Sen UK, Sinha S, Dhara A, Mitra S, Sarkar SK. Atomic layer deposited tungsten nitride thin films as a new lithium-ion battery anode. Phys Chem Chem Phys 2015; 17:17445-53. [DOI: 10.1039/c5cp02184g] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Atomic layer deposited WNx thin films are used as a new Li-ion battery anode whose capacity can be enhanced further by depositing the film on a MWCNT scaffold layer.
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Affiliation(s)
- Dip K. Nandi
- Department of Energy Science and Engineering
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - Uttam K. Sen
- Department of Energy Science and Engineering
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - Soumyadeep Sinha
- Department of Energy Science and Engineering
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - Arpan Dhara
- Department of Energy Science and Engineering
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - Sagar Mitra
- Department of Energy Science and Engineering
- Indian Institute of Technology Bombay
- Mumbai
- India
| | - Shaibal K. Sarkar
- Department of Energy Science and Engineering
- Indian Institute of Technology Bombay
- Mumbai
- India
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Mukherjee SS, Skoff DR, Middleton CT, Zanni MT. Fully absorptive 3D IR spectroscopy using a dual mid-infrared pulse shaper. J Chem Phys 2013; 139:144205. [PMID: 24116612 PMCID: PMC4108792 DOI: 10.1063/1.4824638] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 09/25/2013] [Indexed: 12/27/2022] Open
Abstract
This paper presents the implementation of 3D IR spectroscopy by adding a second pump beam to a two-beam 2D IR spectrometer. An independent mid-IR pulse shaper is used for each pump beam, which can be programmed to collect its corresponding dimension in either the frequency or time-domains. Due to the phase matching geometry employed here, absorptive 3D IR spectra are automatically obtained, since all four of the rephasing and non-rephasing signals necessary to generate absorptive spectra are collected simultaneously. Phase cycling is used to isolate the fifth-order from the third-order signals. The method is demonstrated on tungsten hexacarbonyl (W(CO)6) and dicarbonylacetylacetonato rhodium (I), for which the eigenstates are extracted up to the third excited state. Pulse shaping affords a high degree of control over 3D IR experiments by making possible mixed time- and frequency-domain experiments, fast data acquisition and straightforward implementation.
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Affiliation(s)
- Sudipta S Mukherjee
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, Wisconsin 53706, USA
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Rosenberg SG, Barclay M, Fairbrother DH. Electron induced reactions of surface adsorbed tungsten hexacarbonyl (W(CO)6). Phys Chem Chem Phys 2013; 15:4002-15. [PMID: 23400276 DOI: 10.1039/c3cp43902j] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Tungsten hexacarbonyl (W(CO)(6)) is frequently used as an organometallic precursor to create metal-containing nanostructures in electron beam induced deposition (EBID). However, the fundamental electron stimulated reactions responsible for both tungsten deposition and the incorporation of carbon and oxygen atom impurities remain unclear. To address this issue we have studied the effect of 500 eV incident electrons on nanometer thick films of W(CO)(6) under Ultra-High Vacuum (UHV) conditions. Results from X-ray Photoelectron Spectroscopy, Mass Spectrometry, and Infrared Spectroscopy reveal that the initial step involves electron stimulated desorption of multiple CO ligands from parent W(CO)(6) molecules and the formation of partially decarbonylated tungsten species (W(x)(CO)(y)). Subsequent electron interactions with these W(x)(CO)(y) species lead to ligand decomposition rather than further CO desorption, ultimately producing oxidized tungsten atoms incorporated in a carbonaceous matrix. The presence of co-adsorbed water during electron irradiation increased the extent of tungsten oxidation. The electron stimulated deposition cross-section of W(CO)(6) at an incident electron energy of 500 eV was calculated to be 6.50 × 10(-16) cm(-2). When considered collectively with findings from previous precursors (MeCpPtMe(3) and Pt(PF(3))(4)), results from the present study are consistent with the idea that the electron induced reactions in EBID are initiated by low energy secondary electrons generated by primary beam-substrate interactions, rather than by the primary beam itself.
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Thon R, Chin W, Galaup JP, Ouvrard A, Bourguignon B, Crépin C. Vibrational Perturbations of W(CO)6 Trapped in a Molecular Lattice Probed by Linear and Nonlinear Spectroscopy. J Phys Chem A 2013; 117:8145-56. [DOI: 10.1021/jp401498e] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Raphaël Thon
- Institut des Sciences Moléculaires d’Orsay UMR 8214, CNRS and Univ. Paris Sud, Bât 210, 91405 Orsay
Cedex, France
| | - Wutharath Chin
- Institut des Sciences Moléculaires d’Orsay UMR 8214, CNRS and Univ. Paris Sud, Bât 210, 91405 Orsay
Cedex, France
| | - Jean-Pierre Galaup
- Laboratoire
Aimé Cotton UPR 3321, CNRS and Univ. Paris Sud, Bât 505, 91405 Orsay Cedex, France
| | - Aimeric Ouvrard
- Institut des Sciences Moléculaires d’Orsay UMR 8214, CNRS and Univ. Paris Sud, Bât 210, 91405 Orsay
Cedex, France
| | - Bernard Bourguignon
- Institut des Sciences Moléculaires d’Orsay UMR 8214, CNRS and Univ. Paris Sud, Bât 210, 91405 Orsay
Cedex, France
| | - Claudine Crépin
- Institut des Sciences Moléculaires d’Orsay UMR 8214, CNRS and Univ. Paris Sud, Bât 210, 91405 Orsay
Cedex, France
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Yan S, Seidel MT, Zhang Z, Leong WK, Tan HS. Ultrafast vibrational relaxation dynamics of carbonyl stretching modes in Os3(CO)12. J Chem Phys 2011; 135:024501. [PMID: 21766951 DOI: 10.1063/1.3606495] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The vibrational relaxation dynamics of the four infrared active carbonyl (CO) stretching normal modes of Os(3)(CO)(12) at 2068 cm(-1), 2034 cm(-1), 2014 cm(-1), and 2002 cm(-1) were measured using broad-band frequency resolved pump-probe spectroscopy. Transient absorption spectra of these modes were collected, and the fundamental, overtone, and combination bands were assigned. The frequency resolved pump-probe traces measured at the fundamental frequencies for the four stretching normal modes exhibited marked differences: the two axial modes at frequencies of 2068 cm(-1) and 2034 cm(-1) yielded similar bi-exponential decay traces, while the two equatorial modes at 2014 cm(-1) and 2002 cm(-1) showed a rising component, in addition to a bi-exponential decay. Due to the independence of the axial and equatorial stretching modes, it is shown that the axial-equatorial combination anharmonicity constants are near zero. This results in the appearance of the pump-probe signals of these combination bands at the same frequencies as the fundamental transitions, thus leading to interference and the resultant anomalous rising features. If unaccounted for, these interferences may lead to erroneous conclusions about the dynamics of these vibrational stretches. To avoid such pitfalls, it is therefore imperative to resolve such ambiguities. A corrected dynamical picture of the equatorial modes can be obtained by varying the center frequency of the pump pulse. The four modes have a slow vibrational excited population decay time of between 400 to 600 ps. We observe no obvious direct vibrational energy transfer between the axial and equatorial CO stretching modes.
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Affiliation(s)
- Suxia Yan
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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Yan S, Seidel MT, Tan HS. Perturbed free induction decay in ultrafast mid-IR pump–probe spectroscopy. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.10.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Preston TJ, Dutta M, Esselman BJ, Kalume A, George L, McMahon RJ, Reid SA, Fleming Crim F. Formation and relaxation dynamics of iso-CH2Cl–I in cryogenic matrices. J Chem Phys 2011; 135:114503. [DOI: 10.1063/1.3633697] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Keyes TE, Forster RJ, Blackledge C. Time resolved spectroscopy of inorganic complexes. SPECTROSCOPIC PROPERTIES OF INORGANIC AND ORGANOMETALLIC COMPOUNDS 2010. [DOI: 10.1039/9781849730853-00211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Time resolved spectroscopy has revolutionised our understanding of photochemical and photophysical reactions of inorganic complexes. In this review, we briefly describe the most common time resolved optical spectroscopic methods applied to inorganic complexes and outline some examples and highlights from the recent literature. The review is not intended to be exhaustive, but highlights key recent papers from coordination chemistry, supramolecular chemistry, carbonyl chemistry and bioinorganic chemistry, as well as, recent insights from ultrafast spectroscopy into the photophysics of important prototypes such as [Ru(bpy)3]2+ and [Cu(dmp)2]+. A brief perspective is then presented which discusses areas where time resolved spectroscopy of inorganic complexes could play a particularly important role in the next few years.
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Affiliation(s)
- Tia E. Keyes
- National Biophotonics and Imaging Platform School of Chemical Sciences, Dublin City University Glasnevin, Dublin 7 Ireland
| | - Robert J. Forster
- National Biophotonics and Imaging Platform School of Chemical Sciences, Dublin City University Glasnevin, Dublin 7 Ireland
| | - Charles Blackledge
- National Biophotonics and Imaging Platform School of Chemical Sciences, Dublin City University Glasnevin, Dublin 7 Ireland
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Zhuang W, Hayashi T, Mukamel S. Kohärente mehrdimensionale Schwingungsspektroskopie von Biomolekülen: Konzepte, Simulationen und Herausforderungen. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200802644] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Zhuang W, Hayashi T, Mukamel S. Coherent multidimensional vibrational spectroscopy of biomolecules: concepts, simulations, and challenges. Angew Chem Int Ed Engl 2009; 48:3750-81. [PMID: 19415637 PMCID: PMC3526115 DOI: 10.1002/anie.200802644] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The response of complex molecules to sequences of femtosecond infrared pulses provides a unique window into their structure, dynamics, and fluctuating environments. Herein we survey the basic principles of modern two-dimensional infrared (2DIR) spectroscopy, which analogous to those of multidimensional NMR spectroscopy. The perturbative approach for computing the nonlinear optical response of coupled localized chromophores is introduced and applied to the amide backbone transitions of proteins, liquid water, membrane lipids, and amyloid fibrils. The signals are analyzed using classical molecular dynamics simulations combined with an effective fluctuating Hamiltonian for coupled localized anharmonic vibrations whose dependence on the local electrostatic environment is parameterized by an ab initio map. Several simulation methods, (cumulant expansion of Gaussian fluctuation, quasiparticle scattering, the stochastic Liouville equations, direct numerical propagation) are surveyed. Chirality-induced techniques which dramatically enhance the resolution are demonstrated. Signatures of conformational and hydrogen-bonding fluctuations, protein folding, and chemical-exchange processes are discussed.
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Affiliation(s)
- Wei Zhuang
- Department of Chemistry, University of California at Irvine, CA 92697-2025, USA
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