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Lacinbala O, Féraud G, Vincent J, Pino T. Aromatic and Acetylenic C-H or C-D Stretching Bands Anharmonicity Detection of Phenylacetylene by UV Laser-Induced Vibrational Emission. J Phys Chem A 2022; 126:4891-4901. [PMID: 35880827 DOI: 10.1021/acs.jpca.2c01436] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The anharmonic infrared (IR) emission spectra of phenylacetylene C6H5CCH and an isotopologue C6H5CCD induced by 193 nm UV excitation have been investigated in the gas phase. The study has been operated with a homemade IR spectrometer enabling to record time- and wavelength-resolved spectra between 2.5 and 4.5 μm, emitted all along the collisional cooling. The analysis is supported by a kinetic Monte Carlo simulation in the vibrational harmonic approximation. For both species, the anharmonic shifts of the acetylenic C-H or C-D stretching modes and the aromatic C-H stretching modes are studied for band positions and bandwidths in terms of the internal energy. For C6H5CCD, the internal energy dependence of the emission intensity band ratio is investigated and rationalized. This work demonstrates the potential of time-resolved IR emission spectroscopy to explore anharmonicity of astrophysically relevant molecules.
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Affiliation(s)
- Ozan Lacinbala
- Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Saclay, CNRS, 91405 Orsay, France
| | - Géraldine Féraud
- CNRS, LERMA, Sorbonne Université, Observatoire de Paris, Université PSL, F-75005, Paris, France
| | - Julien Vincent
- Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Saclay, CNRS, 91405 Orsay, France
| | - Thomas Pino
- Institut des Sciences Moléculaires d'Orsay (ISMO), Université Paris-Saclay, CNRS, 91405 Orsay, France
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2
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Mackie CJ, Candian A, Lee TJ, Tielens AGGM. Anharmonicity and the IR Emission Spectrum of Neutral Interstellar PAH Molecules. J Phys Chem A 2022; 126:3198-3209. [PMID: 35544706 DOI: 10.1021/acs.jpca.2c01849] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The characteristics of the CH stretching and out-of-plane bending modes in polycyclic aromatic hydrocarbon molecules are investigated using anharmonic density functional theory (DFT) coupled to a vibrational second-order perturbation treatment taking resonance effects into account. The results are used to calculate the infrared emission spectrum of vibrationally excited species in the collision-less environment of interstellar space. This model follows the energy cascade as the molecules relax after the absorption of a UV photon in order to calculate the detailed profiles of the infrared bands. The results are validated against elegant laboratory spectra of polycyclic aromatic hydrocarbon absorption and emission spectra obtained in molecular beams. The factors which influence the peak position, spectral detail, and relative strength of the CH stretching and out-of-plane bending modes are investigated, and detailed profiles for these modes are derived. These are compared to observations of astronomical objects in space, and the implications for our understanding of the characteristics of the molecular inventory of space are assessed.
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Affiliation(s)
- Cameron J Mackie
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Alessandra Candian
- van 't Hoff Institute for Molecular Science, University of Amsterdam, P.O. Box 94157, 1090 GD Amsterdam, The Netherlands
| | - Timothy J Lee
- NASA Ames Research Center, Moffett Field, California 94035-1000, United States
| | - Alexander G G M Tielens
- Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden, The Netherlands.,Astronomy Department, University of Maryland, College Park, Maryland 20742, United States
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3
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Chakraborty S, Mulas G, Rapacioli M, Joblin C. Anharmonic Infrared Spectra of Thermally Excited Pyrene (C 16H 10): A Combined View of DFT-Based GVPT2 with AnharmonicCaOs, and Approximate DFT Molecular dynamics with DemonNano. JOURNAL OF MOLECULAR SPECTROSCOPY 2021; 378:111466. [PMID: 34257467 PMCID: PMC7611198 DOI: 10.1016/j.jms.2021.111466] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The study of the Aromatic Infrared Bands (AIBs) in astronomical environments has opened interesting spectroscopic questions on the effect of anharmonicity on the infrared (IR) spectrum of hot polycyclic aromatic hydrocarbons (PAHs) and related species in isolated conditions. The forthcoming James Webb Space Telescope will unveil unprecedented spatial and spectral details in the AIB spectrum; significant advancement is thus necessary now to model the infrared emission of PAHs, their presumed carriers, with enough detail to exploit the information content of the AIBs. This requires including anharmonicity in such models, and to do so systematically for all species included, requiring a difficult compromise between accuracy and efficiency. We performed a benchmark study to compare the performances of two methods in calculating anharmonic spectra, comparing them to available experimental data. One is a full quantum method, AnharmoniCaOs, relying on an ab initio potential, and the other relies on Molecular Dynamics simulations using a Density Functional based Tight Binding potential. The first one is found to be very accurate and detailed, but it becomes computationally very expensive for increasing temperature; the second is faster and can be used for arbitrarily high temperatures, but is less accurate. Still, its results can be used to model the evolution with temperature of isolated bands. We propose a new recipe to model anharmonic AIB emission using minimal assumptions on the general behaviour of band positions and widths with temperature, which can be defined by a small number of empirical parameters. Modelling accuracy will depend critically on these empirical parameters, allowing for an incremental improvement in model results, as better estimates become gradually available.
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Affiliation(s)
- Shubhadip Chakraborty
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse (UPS), CNRS, CNES, 9 Av. du Colonel Roche, 31028 Toulouse Cedex 4, France
| | - Giacomo Mulas
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse (UPS), CNRS, CNES, 9 Av. du Colonel Roche, 31028 Toulouse Cedex 4, France
- Istituto Nazionale di Astrofisica (INAF), Osservatorio Astronomico di Cagliari, 09047 Selargius (CA), Italy
| | - Mathias Rapacioli
- Laboratoire de Chimie et Physique Quantiques (LCPQ/IRSAMC), Université de Toulouse (UPS),CNRS, 118 Route de Narbonne, 31062 Toulouse, France
| | - Christine Joblin
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse (UPS), CNRS, CNES, 9 Av. du Colonel Roche, 31028 Toulouse Cedex 4, France
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Chakraborty S, Mulas G, Demyk K, Joblin C. Experimental Approach to the Study of Anharmonicity in the Infrared Spectrum of Pyrene from 14 to 723 K. J Phys Chem A 2019; 123:4139-4148. [PMID: 31002512 PMCID: PMC6557715 DOI: 10.1021/acs.jpca.8b11016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Quantifying the effect of anharmonicity on the infrared spectrum of large molecules such as polycyclic aromatic hydrocarbons (PAHs) at high temperatures is the focus of a number of theoretical and experimental studies, many of them motivated by astrophysical applications. We recorded the IR spectrum of pyrene C16H10 microcrystals embedded in KBr pellets over a wide range of temperatures (14-723 K) and studied the evolution of band positions, widths, and integrated intensities with temperature. We identified jumps for some of the spectral characteristics of some bands in the 423-473 K range. These were attributed to a change of phase from crystal to molten in condensed pyrene, which appears to affect more strongly bands involving large CH motions. Empirical anharmonicity factors that quantify the linear evolution of band positions and widths with temperature for values larger than ∼150-250 K, depending on the band, were retrieved from both phases and averaged to provide recommended values for these anharmonicity factors. The derived values were found to be consistent with available gas phase data. We conclude about the relevance of the methodology to produce data that can be compared with calculated anharmonic IR spectra and provide input for models that simulate the IR emission of astro-PAHs.
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Affiliation(s)
- Shubhadip Chakraborty
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, CNRS, CNES, 9 Av. du Colonel Roche, 31028 Toulouse Cedex 4, France
| | - Giacomo Mulas
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, CNRS, CNES, 9 Av. du Colonel Roche, 31028 Toulouse Cedex 4, France
- Istituto Nazionale di Astrofisica (INAF), Osservatorio Astronomico di Cagliari, 09047 Selargius (CA), Italy
| | - Karine Demyk
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, CNRS, CNES, 9 Av. du Colonel Roche, 31028 Toulouse Cedex 4, France
| | - Christine Joblin
- Institut de Recherche en Astrophysique et Planétologie, Université de Toulouse, CNRS, CNES, 9 Av. du Colonel Roche, 31028 Toulouse Cedex 4, France
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5
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Mulas G, Falvo C, Cassam-Chenaï P, Joblin C. Anharmonic vibrational spectroscopy of polycyclic aromatic hydrocarbons (PAHs). J Chem Phys 2018; 149:144102. [PMID: 30316271 DOI: 10.1063/1.5050087] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
While powerful techniques exist to accurately account for anharmonicity in vibrational molecular spectroscopy, they are computationally very expensive and cannot be routinely employed for large species and/or at non-zero vibrational temperatures. Motivated by the study of Polycyclic Aromatic Hydrocarbon (PAH) emission in space, we developed a new code, which takes into account all modes and can describe all infrared transitions including bands becoming active due to resonances as well as overtone, combination, and difference bands. In this article, we describe the methodology that was implemented and discuss how the main difficulties were overcome, so as to keep the problem tractable. Benchmarking with high-level calculations was performed on a small molecule. We carried out specific convergence tests on two prototypical PAHs, pyrene (C16H10) and coronene (C24H12), aiming at optimising tunable parameters to achieve both acceptable accuracy and computational costs for this class of molecules. We then report the results obtained at 0 K for pyrene and coronene, comparing the calculated spectra with available experimental data. The theoretical band positions were found to be significantly improved compared to harmonic density functional theory calculations. The band intensities are in reasonable agreement with experiments, the main limitation being the accuracy of the underlying calculations of the quartic force field. This is a first step toward calculating moderately high-temperature spectra of PAHs and other similarly rigid molecules using Monte Carlo sampling.
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Affiliation(s)
- Giacomo Mulas
- IRAP, Université de Toulouse, CNRS, UPS, CNES, 9 Av. du Colonel Roche, 31028 Toulouse Cedex 4, France
| | - Cyril Falvo
- Institut des Sciences Moléculaires d'Orsay (ISMO), CNRS, University of Paris-Sud, Université Paris-Saclay, 91405 Orsay, France
| | | | - Christine Joblin
- IRAP, Université de Toulouse, CNRS, UPS, CNES, 9 Av. du Colonel Roche, 31028 Toulouse Cedex 4, France
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6
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Mackie CJ, Chen T, Candian A, Lee TJ, Tielens AGGM. Fully anharmonic infrared cascade spectra of polycyclic aromatic hydrocarbons. J Chem Phys 2018; 149:134302. [DOI: 10.1063/1.5038725] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Cameron J. Mackie
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden, The Netherlands
| | - Tao Chen
- Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden, The Netherlands
- Department of Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, 10691 Stockholm, Sweden
| | - Alessandra Candian
- Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA Leiden, The Netherlands
| | - Timothy J. Lee
- NASA Ames Research Center, Moffett Field, California 94035-1000, USA
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7
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Thomas PS, Carrington T, Agarwal J, Schaefer HF. Using an iterative eigensolver and intertwined rank reduction to compute vibrational spectra of molecules with more than a dozen atoms: Uracil and naphthalene. J Chem Phys 2018; 149:064108. [DOI: 10.1063/1.5039147] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Affiliation(s)
- Phillip S. Thomas
- Chemistry Department, Queen’s University, Kingston, Ontario K7L 3N6, Canada
| | - Tucker Carrington
- Chemistry Department, Queen’s University, Kingston, Ontario K7L 3N6, Canada
| | - Jay Agarwal
- Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602-0525, USA
| | - Henry F. Schaefer
- Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602-0525, USA
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8
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Nandi S, Saha A, Patel P, Khan NUH, Kureshy RI, Panda AB. Hydrogenation of Furfural with Nickel Nanoparticles Stabilized on Nitrogen-Rich Carbon Core-Shell and Its Transformations for the Synthesis of γ-Valerolactone in Aqueous Conditions. ACS APPLIED MATERIALS & INTERFACES 2018; 10:24480-24490. [PMID: 29978701 DOI: 10.1021/acsami.8b04239] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
In this article, we report the synthesis of nitrogen-rich carbon layer-encapsulated Ni(0) nanoparticles as a core-shell structure (Ni@N/C-g-800) for the catalytic hydrogenation of furfural to furfuryl alcohol. The nickel nanoparticles were stabilized by the nitrogen-rich graphitic framework, which formed during the agitation of nickel acetate-impregnated cucurbit[6]uril surface in a reducing atmosphere. Furthermore, the catalyst was characterized using various physicochemical methods such as powder X-ray diffraction, Raman, field emission-scanning electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, Brunauer-Emmett-Teller surface area, CO2-temperature-programmed desorption, inductive coupled plasma, and CHN analyses. The nitrogen-rich environment of the solid support with metallic Ni nanoparticles was found to be active and selective for the catalytic hydrogenation of furfural with molecular H2 in an aqueous medium at 100 °C. To understand the reaction mechanism, the diffuse reflectance infrared Fourier transform study was performed, which revealed that the C═O bond is activated in the presence of a catalyst. In addition, we have extended our methodology toward the synthesis of "levulinic acid" and "γ-valerolactone", by successive hydrolysis and hydrogenation of furfuryl alcohol and levulinic acid, respectively, in an aqueous medium. Moreover, the heterogeneous catalysts used in all of the three consecutive steps help in recovery and recycling of the catalyst and easy separation of products.
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Affiliation(s)
| | | | - Parth Patel
- Charotar University of Science and Technology , Changa, Anand 388 421 , Gujarat , India
| | - Noor-Ul H Khan
- Charotar University of Science and Technology , Changa, Anand 388 421 , Gujarat , India
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9
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Baldauf C, Rossi M. Going clean: structure and dynamics of peptides in the gas phase and paths to solvation. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:493002. [PMID: 26598600 DOI: 10.1088/0953-8984/27/49/493002] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The gas phase is an artificial environment for biomolecules that has gained much attention both experimentally and theoretically due to its unique characteristic of providing a clean room environment for the comparison between theory and experiment. In this review we give an overview mainly on first-principles simulations of isolated peptides and the initial steps of their interactions with ions and solvent molecules: a bottom up approach to the complexity of biological environments. We focus on the accuracy of different methods to explore the conformational space, the connections between theory and experiment regarding collision cross section evaluations and (anharmonic) vibrational spectra, and the challenges faced in this field.
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Affiliation(s)
- Carsten Baldauf
- Fritz Haber Institute, Faradayweg 4-6, 14195 Berlin, Germany
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10
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Alata I, Scuderi D, Lepere V, Steinmetz V, Gobert F, Thiao-Layel L, Le Barbu-Debus K, Zehnacker-Rentien A. Exotic Protonated Species Produced by UV-Induced Photofragmentation of a Protonated Dimer: Metastable Protonated Cinchonidine. J Phys Chem A 2015; 119:10007-15. [DOI: 10.1021/acs.jpca.5b06506] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ivan Alata
- Institut des Sciences
Moléculaires d’Orsay (ISMO), CNRS, Univ Paris-Sud, Université Paris Saclay, F-91405 Orsay, France
| | - Debora Scuderi
- Laboratoire de
Chimie Physique (LCP), CNRS, Univ Paris-Sud, Université Paris Saclay, F-91405 Orsay, France
| | - Valeria Lepere
- Institut des Sciences
Moléculaires d’Orsay (ISMO), CNRS, Univ Paris-Sud, Université Paris Saclay, F-91405 Orsay, France
| | - Vincent Steinmetz
- Laboratoire de
Chimie Physique (LCP), CNRS, Univ Paris-Sud, Université Paris Saclay, F-91405 Orsay, France
| | - Fabrice Gobert
- Laboratoire de
Chimie Physique (LCP), CNRS, Univ Paris-Sud, Université Paris Saclay, F-91405 Orsay, France
| | - Loïc Thiao-Layel
- Laboratoire de
Chimie Physique (LCP), CNRS, Univ Paris-Sud, Université Paris Saclay, F-91405 Orsay, France
| | - Katia Le Barbu-Debus
- Institut des Sciences
Moléculaires d’Orsay (ISMO), CNRS, Univ Paris-Sud, Université Paris Saclay, F-91405 Orsay, France
| | - Anne Zehnacker-Rentien
- Institut des Sciences
Moléculaires d’Orsay (ISMO), CNRS, Univ Paris-Sud, Université Paris Saclay, F-91405 Orsay, France
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11
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Calvo F, Li Y, Kiawi DM, Bakker JM, Parneix P, Janssens E. Nonlinear effects in infrared action spectroscopy of silicon and vanadium oxide clusters: experiment and kinetic modeling. Phys Chem Chem Phys 2015. [DOI: 10.1039/c5cp02304a] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Nonlinear effects in infrared action spectroscopy are experimentally quantified and successfully modeled for different inorganic clusters.
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Affiliation(s)
- Florent Calvo
- Laboratoire Interdisciplinaire de Physique
- Rue de La Piscine
- Campus Saint Martin d'Hères
- 38000 Grenoble
- France
| | - Yejun Li
- Laboratory of Solid State Physics and Magnetism
- KU Leuven
- B-3001 Leuven
- Belgium
| | - Denis M. Kiawi
- Radboud University
- Institute for Molecules and Materials
- FELIX Laboratory
- 6525 ED Nijmegen
- The Netherlands
| | - Joost M. Bakker
- Radboud University
- Institute for Molecules and Materials
- FELIX Laboratory
- 6525 ED Nijmegen
- The Netherlands
| | - Pascal Parneix
- Institut des Sciences Moléculaires d'Orsay
- UMR CNRS 8214
- Université Paris Sud 11
- F91405 Orsay Cedex
- France
| | - Ewald Janssens
- Laboratory of Solid State Physics and Magnetism
- KU Leuven
- B-3001 Leuven
- Belgium
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12
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Simon A, Spiegelman F. Water clusters adsorbed on polycyclic aromatic hydrocarbons: Energetics and conformational dynamics. J Chem Phys 2013; 138:194309. [DOI: 10.1063/1.4805015] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [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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Parneix P, Basire M, Calvo F. Accurate modeling of infrared multiple photon dissociation spectra: the dynamical role of anharmonicities. J Phys Chem A 2013; 117:3954-9. [PMID: 23581979 DOI: 10.1021/jp402459f] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The dynamical response of a molecular system to a macropulse typically produced by a free-electron laser is theoretically modeled over experimentally long times, within a realistic kinetic Monte Carlo framework that incorporates absorption, stimulated emission, spontaneous emission, and dissociation events. The simulation relies on an anharmonic potential energy surface obtained from quantum chemistry calculations. Application to cationic naphthalene yields a better agreement with measurements than the anharmonic linear absorption spectrum, thus emphasizing the importance of specific dynamical effects on the spectral properties.
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Affiliation(s)
- Pascal Parneix
- Institut des Sciences Moléculaires d'Orsay, UMR CNRS 8214, Université Paris Sud 11, Bât. 210, F91405 Orsay Cedex, France.
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14
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Pirali O, Goubet M, Huet TR, Georges R, Soulard P, Asselin P, Courbe J, Roy P, Vervloet M. The far infrared spectrum of naphthalene characterized by high resolution synchrotron FTIR spectroscopy and anharmonic DFT calculations. Phys Chem Chem Phys 2013; 15:10141-50. [DOI: 10.1039/c3cp44305a] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Falvo C, Friha H, Pino T, Dhaouadi Z, Parneix P, Calvo F, Bréchignac P. Effects of hydrogen dissociation on the infrared emission spectra of naphthalene: theoretical modeling. Phys Chem Chem Phys 2013; 15:10241-50. [DOI: 10.1039/c3cp44703k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Falvo C, Calvo F, Parneix P. Probing the spin multiplicity of gas-phase polycyclic aromatic hydrocarbons through their infrared emission spectrum: a theoretical study. J Chem Phys 2012; 137:064303. [PMID: 22897269 DOI: 10.1063/1.4739468] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The anharmonic infrared emission spectrum following an optical excitation has been calculated for a variety of polycyclic aromatic hydrocarbon molecules in their ground singlet electronic state or in their triplet state. The computational protocol relies on second-order perturbation theory and involves a quartic vibrational Hamiltonian, the vibrational quantum numbers being sampled according to a Monte Carlo procedure. In the case of neutral naphthalene, the IR spectrum obtained in the (ground) singlet state differs significantly from the spectrum in the triplet state, especially for out-of-plane CH bending modes. Although not as prominent, spectral differences in larger molecules are still observable.
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Affiliation(s)
- Cyril Falvo
- Institut des Sciences Moléculaires d'Orsay, UMR CNRS 8214, Université Paris Sud, F91405 Orsay Cedex, France.
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17
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Parneix P, Basire M, Calvo F. Time-resolved infrared emission spectra of naphthalene under gas phase laboratory and astrophysical conditions. COMPUT THEOR CHEM 2012. [DOI: 10.1016/j.comptc.2011.12.014] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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18
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Van-Oanh NT, Falvo C, Calvo F, Lauvergnat D, Basire M, Gaigeot MP, Parneix P. Improving anharmonic infrared spectra using semiclassically prepared molecular dynamics simulations. Phys Chem Chem Phys 2012; 14:2381-90. [DOI: 10.1039/c2cp23101h] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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19
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Soudan JM, Basire M, Mestdagh JM, Angelié C. A new Monte Carlo method for getting the density of states of atomic cluster systems. J Chem Phys 2011; 135:144109. [PMID: 22010700 DOI: 10.1063/1.3647333] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A novel Monte Carlo flat histogram algorithm is proposed to get the classical density of states in terms of the potential energy, g(E(p)), for systems with continuous variables such as atomic clusters. It aims at avoiding the long iterative process of the Wang-Landau method and controlling carefully the convergence, but keeping the ability to overcome energy barriers. Our algorithm is based on a preliminary mapping in a series of points (called a σ-mapping), obtained by a two-parameter local probing of g(E(p)), and it converges in only two subsequent reweighting iterations on large intervals. The method is illustrated on the model system of a 432 atom cluster bound by a Rydberg type potential. Convergence properties are first examined in detail, particularly in the phase transition zone. We get g(E(p)) varying by a factor 10(3700) over the energy range [0.01 < E(p) < 6000 eV], covered by only eight overlapping intervals. Canonical quantities are derived, such as the internal energy U(T) and the heat capacity C(V)(T). This reveals the solid to liquid phase transition, lying in our conditions at the triple point. This phase transition is further studied by computing a Lindemann-Berry index, the atomic cluster density n(r), and the pressure, demonstrating the progressive surface melting at this triple point. Some limited results are also given for 1224 and 4044 atom clusters.
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Affiliation(s)
- J-M Soudan
- Laboratoire Francis Perrin, CNRS-URA 2453, CEA, IRAMIS, Service des Photons Atomes et Molécules, F-91191 Gif-sur-Yvette Cedex, France.
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20
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Calvo F, Basire M, Parneix P. Temperature effects on the rovibrational spectra of pyrene-based PAHs. J Phys Chem A 2011; 115:8845-54. [PMID: 21786804 DOI: 10.1021/jp202935p] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Absorption infrared spectra have been computed for a variety of polycyclic aromatic hydrocarbon molecules of the pyrene family, taking into account anharmonicity and temperature effects, rovibrational quantization, and couplings. The energy levels are described by a second-order perturbative expansion of the rovibrational Hamiltonian in the vibrational and rotational quantum numbers, as relevant for a symmetric-top molecule, with ingredients obtained from quantum chemistry calculations. Multicanonical Monte Carlo simulations are carried out to compute bidimensional IR intensity histograms as a function of total energy and vibrational frequency, which then provide the absorption spectrum at arbitrary temperatures via a Laplace transformation. The main spectral features analyzed for neutral, anionic, and cationic pyrene indicate a strong dependence on temperature, in agreement with existing laboratory experiments, and a significant contribution of rotational degrees of freedom to the overall broadenings. The spectral shifts and broadenings reveal some sensitivity of anharmonicities to the charge and protonation states and, in the case of protonated pyrene and pyrenyl cation, on possible isomers and between aromatic and aliphatic C-H bands. Implications of the present work to the general issue of interstellar emission features are discussed.
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Affiliation(s)
- F Calvo
- LASIM, Université de Lyon and CNRS UMR 5579, 43 Bd du 11 Novembre 1918, F69622 Villeurbanne Cedex, France.
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Basire M, Parneix P, Pino T, Bréchignac P, Calvo F. Modeling the anharmonic infrared Emission Spectra of PAHs: Application to the Pyrene Cation. ACTA ACUST UNITED AC 2011. [DOI: 10.1051/eas/1146009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Simon A, Rapacioli M, Lanza M, Joalland B, Spiegelman F. Molecular dynamics simulations on [FePAH]+ π-complexes of astrophysical interest: anharmonic infrared spectroscopy. Phys Chem Chem Phys 2011; 13:3359-74. [PMID: 21243160 DOI: 10.1039/c0cp00990c] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this article, classical Born-Oppenheimer molecular dynamics (MD) simulations in the microcanonical ensemble are performed on neutral and cationic polycyclic aromatic hydrocarbon (PAH) species, focusing on [FePAH](+)π-complexes. Their anharmonic mid-infrared (mid-IR) spectra in the classical approximation are derived. This approach allows us to describe the influence of the energy of a system on its IR spectrum in terms of band-shifts and broadenings. The MD simulations are performed on a potential energy surface (PES) described at the self-consistent-charge density functional tight-binding level of theory. The PES is benchmarked on DFT calculations, showing the validity of the approach for complexes of Fe(+) with PAHs larger than coronene (C(24)H(12)) that are of astrophysical interest. MD simulations at high temperature show the occurrence of the diffusion of the Fe cation on the surface of the PAH. It proceeds through the edge of the carbon skeleton which is the lowest energy pathway presenting barriers smaller than 1 eV. Although only qualitative information on the band broadenings can be obtained, we show that the dependence of the computed positions of the main bands of [C(24)H(12)](0/+)and [FeC(24)H(12)](+)π-complexes on temperature can be fit by linear laws. The spectral trends determined for [FeC(24)H(12)](+) are compared to those of N-substituted [C(23)NH(12)](+)and [SiC(24)H(12)](+)π-complexes of astrophysical interest.
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Affiliation(s)
- Aude Simon
- Laboratoire de Chimie et Physique Quantiques, IRSAMC, Université de Toulouse, UPS, LCPQ, 118 Route de Narbonne, F-31062 Toulouse, France.
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23
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Calvo F, Parneix P, Van-Oanh NT. Finite-temperature infrared spectroscopy of polycyclic aromatic hydrocarbon molecules. II. Principal mode analysis and self-consistent phonons. J Chem Phys 2010; 133:074303. [DOI: 10.1063/1.3465554] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Pauzat F, Pilmé J, Toulouse J, Ellinger Y. About the collapse of the 3.3 μm CH stretching band with ionization in polycyclic aromatic hydrocarbons: Configuration interaction and quantum Monte Carlo studies of the CH fragment. J Chem Phys 2010; 133:054301. [DOI: 10.1063/1.3465552] [Citation(s) in RCA: 15] [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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Calvo F, Parneix P, Van-Oanh NT. Finite temperature infrared spectroscopy of polycyclic aromatic hydrocarbon molecules: Path-integral molecular dynamics. J Chem Phys 2010; 132:124308. [DOI: 10.1063/1.3367719] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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27
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Basire M, Parneix P, Calvo F. Finite-Temperature IR Spectroscopy of Polyatomic Molecules: A Theoretical Assessment of Scaling Factors. J Phys Chem A 2009; 114:3139-46. [DOI: 10.1021/jp9088639] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Basire
- Laboratoire de Photophysique Moléculaire,∥ C.N.R.S. Fédération de recherche Lumière Matière, Bat 210, Université Paris Sud 11, F91405 Orsay Cedex, France, and LASIM, Université de Lyon and CNRS UMR 5579, 43 Bd du 11 Novembre 1918, F69622 Villeurbanne Cedex, France
| | - P. Parneix
- Laboratoire de Photophysique Moléculaire,∥ C.N.R.S. Fédération de recherche Lumière Matière, Bat 210, Université Paris Sud 11, F91405 Orsay Cedex, France, and LASIM, Université de Lyon and CNRS UMR 5579, 43 Bd du 11 Novembre 1918, F69622 Villeurbanne Cedex, France
| | - F. Calvo
- Laboratoire de Photophysique Moléculaire,∥ C.N.R.S. Fédération de recherche Lumière Matière, Bat 210, Université Paris Sud 11, F91405 Orsay Cedex, France, and LASIM, Université de Lyon and CNRS UMR 5579, 43 Bd du 11 Novembre 1918, F69622 Villeurbanne Cedex, France
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