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Goli M, Shahbazian S. MC-QTAIM analysis reveals an exotic bond in coherently quantum superposed malonaldehyde. Phys Chem Chem Phys 2023; 25:5718-5730. [PMID: 36744327 DOI: 10.1039/d2cp05499j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The proton between the two oxygen atoms of the malonaldehyde molecule experiences an effective double-well potential in which the proton's wavefunction is delocalized between the two wells. Herein we employ a state-of-the-art multi-component quantum theory of atoms in molecules partitioning scheme to obtain the molecular structure, i.e. atoms in molecules and bonding network, from the superposed ab initio wavefunctions of malonaldehyde. In contrast to the familiar clamped-proton portrayal of malonaldehyde, in which the proton forms a hydrogen basin, for the superposed states the hydrogen basin disappears and two novel hybrid oxygen-hydrogen basins appear instead, with an even distribution of the proton population between the two basins. The interaction between the hybrid basins is stabilizing thanks to an unprecedented mechanism. This involves the stabilizing classical Coulomb interaction of the one-proton density in one of the basins with one-electron density in the other basin. This stabilizing mechanism yields a bond foreign to the known bonding modes in chemistry.
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Affiliation(s)
- Mohammad Goli
- School of Nano Science, Institute for Research in Fundamental Sciences (IPM), Tehran 19395-5531, Iran.
| | - Shant Shahbazian
- Department of Physics, Shahid Beheshti University, Evin, Tehran, Iran.
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2
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Lozynski M, Rusinska-Roszak D. Finding the direct energy-structure correlations in intramolecular aromaticity assisted hydrogen bonding (AAHB). J Mol Graph Model 2021; 105:107884. [PMID: 33725643 DOI: 10.1016/j.jmgm.2021.107884] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 02/25/2021] [Accepted: 02/25/2021] [Indexed: 11/25/2022]
Abstract
A predictive model for intramolecular hydrogen bond energy (EHB) calculation of polyaromatic ortho-hydroxyaldehydes based on a set of small, functionalized hydrocarbons is developed. The complete data set of 18 compounds was used for this study. The model is based on one of four optional categories of molecular descriptors: geometric, spectroscopic, bond order and topological indices. The model of Wiberg bond indices (WBIs) as descriptors of the CC involved bond based on stepwise regression has acceptable prediction abilities for 14 structures of ortho-hydroxyformylobenzo[a]pyrene derivatives already at the semiempirical level. The presented correlation enables a significantly more rapid and quantitative description of the hydrogen bonding strength than the much more time-consuming MTA method. Thus, WBIs are shown to provide a reliable means for fast prescreening of the energy of chelate hydrogen bonds potentially for any polyaromatic derivatives.
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Affiliation(s)
- Marek Lozynski
- Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965, Poznan, Poland
| | - Danuta Rusinska-Roszak
- Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965, Poznan, Poland.
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Nandipati KR, Kanakati AK, Singh H, Mahapatra S. Controlled intramolecular H-transfer in malonaldehyde in the electronic ground state mediated through the conical intersection of 1nπ* and 1ππ* excited electronic states. Phys Chem Chem Phys 2019; 21:20018-20030. [PMID: 31478035 DOI: 10.1039/c9cp03762d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report photo-isomerization of malonaldehyde in its electronic ground state (S0), mediated by coupled 1nπ*(S1)-1ππ*(S2) excited electronic states, accomplished with the aid of optimally designed ultraviolet (UV)-laser pulses. In particular, control of H-transfer from a configuration predominantly located in the left well (say, reactant) to that in the right well (say, product) of the electronic ground S0 potential energy surface is achieved by a pump-dump mechanism including the nonadiabatic interactions between the excited S1 and S2 states. An interplay between the nonadiabatic coupling due to the conical intersection of the S1 and S2 states and the laser-molecule interaction is found to be imprinted in the time-dependent electronic population. The latter is also examined by employing optimal fields of varying intensities and frequencies of the UV laser pulses. For the purpose of the present study, we constructed a three-state and two-mode coupled diabatic Hamiltonian with the help of adiabatic electronic energies and transition dipole moments calculated by ab initio quantum chemistry methods. The electronic diabatic model is developed using the calculated adiabatic energies of the two excited electronic states (S1 and S2) in order to carry out the dynamics study. The optimal fields for achieving the controlled isomerization are designed within the framework of optimal control theory employing the optimization technique of a multitarget functional using the genetic algorithm. The laser-driven dynamics of the system is treated by numerically solving the time-dependent Schrödinger equation within the dipole approximation. A time-averaged yield of the target product of ∼40% is achieved in the present treatment of dynamics with optimal laser pulses.
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Affiliation(s)
- K R Nandipati
- School of Chemistry, University of Hyderabad, Hyderabad, 500 046, India.
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Karandashev K, Xu ZH, Meuwly M, Vaníček J, Richardson JO. Kinetic isotope effects and how to describe them. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2017; 4:061501. [PMID: 29282447 PMCID: PMC5729036 DOI: 10.1063/1.4996339] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2017] [Accepted: 08/23/2017] [Indexed: 06/01/2023]
Abstract
We review several methods for computing kinetic isotope effects in chemical reactions including semiclassical and quantum instanton theory. These methods describe both the quantization of vibrational modes as well as tunneling and are applied to the ⋅H + H2 and ⋅H + CH4 reactions. The absolute rate constants computed with the semiclassical instanton method both using on-the-fly electronic structure calculations and fitted potential-energy surfaces are also compared directly with exact quantum dynamics results. The error inherent in the instanton approximation is found to be relatively small and similar in magnitude to that introduced by using fitted surfaces. The kinetic isotope effect computed by the quantum instanton is even more accurate, and although it is computationally more expensive, the efficiency can be improved by path-integral acceleration techniques. We also test a simple approach for designing potential-energy surfaces for the example of proton transfer in malonaldehyde. The tunneling splittings are computed, and although they are found to deviate from experimental results, the ratio of the splitting to that of an isotopically substituted form is in much better agreement. We discuss the strengths and limitations of the potential-energy surface and based on our findings suggest ways in which it can be improved.
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Affiliation(s)
- Konstantin Karandashev
- Laboratory of Theoretical Physical Chemistry, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Zhen-Hao Xu
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland
| | - Markus Meuwly
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, CH-4056 Basel, Switzerland
| | - Jiří Vaníček
- Laboratory of Theoretical Physical Chemistry, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Jeremy O Richardson
- Laboratory of Physical Chemistry, Department of Chemistry and Applied Biosciences, Eidgenössische Technische Hochschule Zürich (ETHZ), CH-8093 Zürich, Switzerland
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6
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Lin C, Kumar M, Finney BA, Francisco JS. Intramolecular hydrogen bonding in malonaldehyde and its radical analogues. J Chem Phys 2017; 147:124309. [PMID: 28964036 DOI: 10.1063/1.4996563] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
High level Brueckner doubles with triples correction method-based ab initio calculations have been used to investigate the nature of intramolecular hydrogen bonding and intramolecular hydrogen atom transfer in cis-malonaldehyde (MA) and its radical analogues. The radicals considered here are the ones that correspond to the homolytic cleavage of C-H bonds in cis-MA. The results suggest that cis-MA and its radical analogues, cis-MARS, and cis-MARA, both exist in planar geometry. The calculated intramolecular O-H⋯O=C bond in cis-MA is shorter than that in the radical analogues. The intramolecular hydrogen bond in cis-MA is stronger than in its radicals by at least 3.0 kcal/mol. The stability of a cis-malonaldehyde radical correlates with the extent of electron spin delocalization; cis-MARA, in which the radical spin is more delocalized, is the most stable MA radical, whereas cis-MARS, in which the radical spin is strongly localized, is the least stable radical. The natural bond orbital analysis indicates that the intramolecular hydrogen bonding (O⋯H⋯O) in cis-malonaldehyde radicals is stabilized by the interaction between the lone pair orbitals of donor oxygen and the σ* orbital of acceptor O-H bond (n → σ*OH). The calculated barriers indicate that the intramolecular proton transfer in cis-MA involves 2.2 kcal/mol lower barrier than that in cis-MARS.
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Affiliation(s)
- Chen Lin
- Department of Chemistry and Department of Earth and Atmospheric Science, Purdue University, West Lafayette, Indiana 47907-1393, USA
| | - Manoj Kumar
- Department of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588-0321, USA
| | - Brian A Finney
- Department of Chemistry and Department of Earth and Atmospheric Science, Purdue University, West Lafayette, Indiana 47907-1393, USA
| | - Joseph S Francisco
- Department of Chemistry and Department of Earth and Atmospheric Science, Purdue University, West Lafayette, Indiana 47907-1393, USA
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Hansen PE, Spanget-Larsen J. NMR and IR Investigations of Strong Intramolecular Hydrogen Bonds. Molecules 2017; 22:E552. [PMID: 28353675 PMCID: PMC6154318 DOI: 10.3390/molecules22040552] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 03/20/2017] [Accepted: 03/24/2017] [Indexed: 11/24/2022] Open
Abstract
For the purpose of this review, strong hydrogen bonds have been defined on the basis of experimental data, such as OH stretching wavenumbers, νOH, and OH chemical shifts, δOH (in the latter case, after correction for ring current effects). Limits for O-H···Y systems are taken as 2800 > νOH > 1800 cm-1, and 19 ppm > δOH > 15 ppm. Recent results as well as an account of theoretical advances are presented for a series of important classes of compounds such as β-diketone enols, β-thioxoketone enols, Mannich bases, proton sponges, quinoline N-oxides and diacid anions. The O···O distance has long been used as a parameter for hydrogen bond strength in O-H···O systems. On a broad scale, a correlation between OH stretching wavenumbers and O···O distances is observed, as demonstrated experimentally as well as theoretically, but for substituted β-diketone enols this correlation is relatively weak.
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Affiliation(s)
- Poul Erik Hansen
- Department of Science and Environment, Roskilde University, Universitetsvej 1, P.O. Box 260, DK-4000 Roskilde, Denmark.
| | - Jens Spanget-Larsen
- Department of Science and Environment, Roskilde University, Universitetsvej 1, P.O. Box 260, DK-4000 Roskilde, Denmark.
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Shayan K, Nowroozi A. The first singlet excited state (S1) intramolecular hydrogen bond of malonaldehyde derivatives: a TD-DFT and CIS study. Struct Chem 2016. [DOI: 10.1007/s11224-016-0796-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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9
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Romero-Fernández MP, Ávalos M, Babiano R, Cintas P, Jiménez JL, Palacios JC. A further look at π-delocalization and hydrogen bonding in 2-arylmalondialdehydes. Tetrahedron 2016. [DOI: 10.1016/j.tet.2015.11.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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10
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Matsui H, Iwamoto K, Mochizuki D, Osada S, Asakura Y, Kuroda K. Proton tunneling in low dimensional cesium silicate LDS-1. J Chem Phys 2015; 143:024503. [DOI: 10.1063/1.4926445] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
- Hiroshi Matsui
- Department of Physics, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
| | - Kei Iwamoto
- Department of Physics, Graduate School of Science, Tohoku University, Sendai 980-8578, Japan
| | - Dai Mochizuki
- Interdisciplinary Cluster for Cutting Edge Research, Center for Energy and Environmental Science, Shinshu University, 3-15-1 Tokida, Ueda, Nagano 386-8567, Japan
| | - Shimon Osada
- Department of Applied Chemistry, Faculty of Science and Engineering, Waseda University, Tokyo 169-8555, Japan
| | - Yusuke Asakura
- Department of Applied Chemistry, Faculty of Science and Engineering, Waseda University, Tokyo 169-8555, Japan
| | - Kazuyuki Kuroda
- Department of Applied Chemistry, Faculty of Science and Engineering, Waseda University, Tokyo 169-8555, Japan
- Kagami Memorial Research Institute for Material Science and Technology, Waseda University, Tokyo 169-0051, Japan
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11
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Howard DL, Kjaergaard HG, Huang J, Meuwly M. Infrared and Near-Infrared Spectroscopy of Acetylacetone and Hexafluoroacetylacetone. J Phys Chem A 2015; 119:7980-90. [DOI: 10.1021/acs.jpca.5b01863] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daryl L. Howard
- Australian Synchrotron, 800 Blackburn
Road, Clayton, Victoria 3168, Australia
- Department
of Chemistry, University of Otago, P.O. Box 56, Dunedin 9016, New Zealand
| | - Henrik G. Kjaergaard
- Department
of Chemistry, University of Otago, P.O. Box 56, Dunedin 9016, New Zealand
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Jing Huang
- Department
of Pharmaceutical Science, University of Maryland, Baltimore, Maryland 21201, United States
- Department
of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Markus Meuwly
- Department
of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
- Department
of Chemistry, Brown University, Providence, Rhode Island 01912, United States
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12
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Pitsevich GA, Malevich AE, Kozlovskaya EN, Doroshenko IY, Pogorelov VE, Sablinskas V, Balevicius V. Theoretical study of the C-H/O-H stretching vibrations in malonaldehyde. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 145:384-393. [PMID: 25795613 DOI: 10.1016/j.saa.2015.02.067] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 12/20/2014] [Accepted: 02/16/2015] [Indexed: 06/04/2023]
Abstract
IR and Raman spectra of the malonaldehyde molecule and its deuterated analogues were calculated in the B3LYP/cc-pVQZ approximation. Anharmonicity effects were taken into account both in the context of a standard model of the second order perturbation theory and by constructing the potential energy surfaces (PES) with a limited number of dimensions using the Cartesian coordinates of the hydroxyl hydrogen atom and the stretching coordinates of С-Н, C-D, O-H, and O-D bonds. It was shown that in each of the two equivalent forms of the molecule, besides the global minimum, an additional local minimum at the PES is formed with the energy more than 3,000 cm(-1) higher than the energy in the global minimum. Calculations carried out by constructing the 2D and 3D PESs indicate a high anharmonicity level and multiple manifestations of the stretching О-Н vibrations, despite the fact that the model used does not take into account the splitting of the ground-state and excited vibrational energy levels. In particular, the vibration with the frequency 3,258 cm(-1) may be associated with proton transfer to the region of a local minimum of energy. Comparing the results obtained with the experimental data presented in the literature allowed us to propose a new variant of bands assignments in IR and Raman spectra of the molecule in the spectral region 2,500-3,500 cm(-1).
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Rusinska-Roszak D, Sowinski G. Estimation of the intramolecular O-H···O═C hydrogen bond energy via the molecular tailoring approach. Part I: aliphatic structures. J Chem Inf Model 2014; 54:1963-77. [PMID: 24921685 DOI: 10.1021/ci500107w] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A simple and universal method for the estimation of the intramolecular hydrogen bond (HB) energy (E(HB)) in hydroxycarbonyl aliphatic compounds is proposed by the application of the molecular tailoring approach (MTA) based on calculations at the second-order Møller-Plesset MP2 level. The calculation of EHB can be realized by the one optimization and three single point calculations of the energy for each compound with carbonyl and hydroxyl groups involved in HB. The intramolecular hydrogen bond energies estimated for 153 structures (of 102 compounds) ranged from 1.4 to 13.7 kcal/mol for systems without resonance-assisted hydrogen bonding (RAHB). To verify the method, we show the correlations of the energy (E(HB)) in six-, seven-, and eight-membered HB rings in the optimized multifunctional molecules with the usual geometry descriptors of hydrogen bonds. Moreover, topological parameters from the atoms in molecules (AIM) theory and the calculated infrared and proton NMR spectra are correlated. The effects of conjugation and π-electron delocalization, bifurcation, and cooperativity are discussed, along with the correlation between the strength and geometrical parameters of H bonding.
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Affiliation(s)
- Danuta Rusinska-Roszak
- Institute of Chemical Technology and Engineering, Poznan University of Technology , Pl. M. Sklodowskiej-Curie 2, 60-965 Poznan, Poland
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Huang J, Buchowiecki M, Nagy T, Vaníček J, Meuwly M. Kinetic isotope effect in malonaldehyde determined from path integral Monte Carlo simulations. Phys Chem Chem Phys 2014; 16:204-11. [DOI: 10.1039/c3cp53698j] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Lüttschwager NO, Wassermann TN, Coussan S, Suhm MA. Vibrational tuning of the Hydrogen transfer in malonaldehyde – a combined FTIR and Raman jet study†. Mol Phys 2013. [DOI: 10.1080/00268976.2013.798042] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Nils O.B. Lüttschwager
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen , Tammannstr. 6, Göttingen, D-37077, Germany
| | - Tobias N. Wassermann
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen , Tammannstr. 6, Göttingen, D-37077, Germany
- Laboratoire PIIM, Université de Provence, Centre Saint-Jérôme , F-13 397 cedex 20, Marseille, France
| | - Stéphane Coussan
- Laboratoire PIIM, Université de Provence, Centre Saint-Jérôme , F-13 397 cedex 20, Marseille, France
| | - Martin A. Suhm
- Institut für Physikalische Chemie, Georg-August-Universität Göttingen , Tammannstr. 6, Göttingen, D-37077, Germany
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Affiliation(s)
- Peter Hamm
- Physikalisch-Chemisches Institut, Universität Zürich , Zürich, Switzerland
| | - Gerhard Stock
- Biomolecular Dynamics, Institute of Physics, Albert Ludwigs University , Freiburg, Germany
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Hamm P, Stock G. Vibrational conical intersections as a mechanism of ultrafast vibrational relaxation. PHYSICAL REVIEW LETTERS 2012; 109:173201. [PMID: 23215183 DOI: 10.1103/physrevlett.109.173201] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2012] [Indexed: 06/01/2023]
Abstract
Presenting true crossings of adiabatic potential energy surfaces, conical intersections are a paradigm of ultrafast and efficient electronic relaxation dynamics. The same mechanism is shown to apply also for vibrational conical intersections, which may occur when two high-frequency modes (such as OH stretch vibrations) are coupled to low-frequency modes (such as hydrogen bonding modes). By derivation of a model Hamiltonian and its parametrization for a concrete example, malonaldehyde, the conditions that such conical intersections occur are identified and the consequences for the vibrational dynamics and spectra are demonstrated.
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Affiliation(s)
- Peter Hamm
- Physikalisch-Chemisches Institut, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland
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Burt MB, Fridgen TD. Gas-Phase Structures of Pb2+-Cationized Phenylalanine and Glutamic Acid Determined by Infrared Multiple Photon Dissociation Spectroscopy and Computational Chemistry. J Phys Chem A 2012; 117:1283-90. [DOI: 10.1021/jp306420e] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Michael B. Burt
- Department of Chemistry, Memorial University of Newfoundland,
St. John’s,
Newfoundland and Labrador, Canada, A1B 3X7
| | - Travis D. Fridgen
- Department of Chemistry, Memorial University of Newfoundland,
St. John’s,
Newfoundland and Labrador, Canada, A1B 3X7
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Conformation, molecular structure, and intramolecular hydrogen bonding of 1,1,1-trifluoro-5,5-dimethyl-2,4-hexanedione. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2012.04.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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20
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Raissi H, Yoosefian M, Mollania F, Khoshkhou S. Electronic structures, intramolecular interactions, and aromaticity of substituted 1-(2-iminoethylidene) silan amine: a density functional study. Struct Chem 2012. [DOI: 10.1007/s11224-012-0038-7] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Bloino J, Biczysko M, Barone V. General Perturbative Approach for Spectroscopy, Thermodynamics, and Kinetics: Methodological Background and Benchmark Studies. J Chem Theory Comput 2012; 8:1015-36. [DOI: 10.1021/ct200814m] [Citation(s) in RCA: 213] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Julien Bloino
- Scuola Normale Superiore, piazza
dei Cavalieri 7, I-56126 Pisa, Italy
- Consiglio Nazionale delle Ricerche, Istituto di Chimica dei Composti Organometallici (CNR-ICCOM), UOS di Pisa, Via G. Moruzzi, 1 I-56124 Italy
| | - Malgorzata Biczysko
- Center for Nanotechnology Innovation
@NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, I-56127
Pisa, Italy
| | - Vincenzo Barone
- Scuola Normale Superiore, piazza
dei Cavalieri 7, I-56126 Pisa, Italy
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Vakili M, Tayyari S, Kanaani A, Nekoei AR, Salemi S, Miremad H, Berenji A, Sammelson R. Conformational stability, molecular structure, intramolecular hydrogen bonding, and vibrational spectra of 5,5-dimethylhexane-2,4-dione. J Mol Struct 2011. [DOI: 10.1016/j.molstruc.2011.04.045] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Yang Y, Meuwly M. A generalized reactive force field for nonlinear hydrogen bonds: hydrogen dynamics and transfer in malonaldehyde. J Chem Phys 2010; 133:064503. [PMID: 20707571 DOI: 10.1063/1.3447701] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Using molecular dynamics (MD) simulations, the spectroscopy and dynamics of malonaldehyde is investigated. To this end, the recently proposed molecular mechanics with proton transfer (MMPT) potential is generalized to nonlinear hydrogen bonds. The calculated properties for malonaldehyde in both gas and condensed phases, including equilibrium geometries, infrared spectra, tunneling splittings, and hydrogen transfer rates, compare well with previous experimental and computational works. In particular, by using a harmonic bath averaged (HBA) Hamiltonian, which is based on a reaction path Hamiltonian, it is possible to estimate the tunneling splitting in an efficient manner. It is found that a zero point corrected barrier of 6.7 kcal/mol and effective masses of 1.234 (i.e., 23.4% larger than the mass of a physical H-atom) and 1.117 (for the physical D-atom) are consistent with the measured splittings of 21.6 and 2.9 cm(-1), respectively. The HBA Hamiltonian also yields a pair of hydrogen transfer fundamentals at 1573 and 1267 cm(-1), similar to results obtained with a reaction surface Hamiltonian on a MP2/6-31G(**) potential energy surface. This amounts to a substantial redshift of more than 1000 cm(-1) which can be rationalized by comparison with weakly (HCO(+): rare gas) and strongly (H(2)O-H(+)-OH(2)) proton-bound systems. Hydrogen transfer rates in vacuum and water were determined from the validated MMPT potential and it is found that the solvent enhances the rate by a factor of 5 at 300 K. The rates of 2.4/ns and 10/ns are commensurate with previous density functional tight binding ab initio MD studies.
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Affiliation(s)
- Yonggang Yang
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
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Vakili M, Tayyari S, Nekoei AR, Miremad H, Salemi S, Sammelson R. Structure, intramolecular hydrogen bonding, and vibrational spectra of 2,2,6,6-tetramethyl-3,5-heptanedione. J Mol Struct 2010. [DOI: 10.1016/j.molstruc.2010.02.072] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lüttschwager NOB, Wassermann TN, Coussan S, Suhm MA. Periodic bond breaking and making in the electronic ground state on a sub-picosecond timescale: OH bending spectroscopy of malonaldehyde in the frequency domain at low temperature. Phys Chem Chem Phys 2010; 12:8201-7. [DOI: 10.1039/c002345k] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Došlić N, Kühn O. The Intramolecular Hydrogen-Bond in Malonaldehyde as Seen by Infrared Spectroscopy. A Four-Dimensional Model Study. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zpch.217.12.1507.20477] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The infrared spectrum of the O–H–O fragment of malonaldehyde is studied using a four-dimensional model. This comprises the OH stretching and the two OH bending vibrations as well an O–O ring deformation mode under the assumption of overall Cs symmetry. The full anharmonic potential energy and dipole moment surfaces are calculated using density functional theory and the respective vibrational eigenvalue problem is solved by an iterative Lanczos method. Fundamental and combination transitions are discussed for the normal species and the symmetrically deuterated isotopomer. Special emphasis is paid to the OH/OD stretching region which reveals the signatures of strong mode mixing what renders a simple assignment in terms of fundamental transitions difficult. In addition results for hot transitions are presented which show a rather different OH/OD band due to the topology of the potential energy surface. The influence of H atom tunneling on the spectrum is briefly addressed employing an alternative three-dimensional model which takes into account the in-plane H atom motion as well as the O–O distance.
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Tayyari SF, Moosavi-Tekyeh Z, Soltanpour M, Berenji AR, Sammelson RE. Structure and vibrational assignment of 3-nitro-2,4-pentanedione: A density functional theoretical study. J Mol Struct 2008. [DOI: 10.1016/j.molstruc.2008.04.058] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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30
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Atkins CG, Rajabi K, Gillis EAL, Fridgen TD. Infrared Multiple Photon Dissociation Spectra of Proton- and Sodium Ion-Bound Glycine Dimers in the N−H and O−H Stretching Region. J Phys Chem A 2008; 112:10220-5. [DOI: 10.1021/jp805514b] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Chad G. Atkins
- Department of Chemistry, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada A1N 4T8
| | - Khadijeh Rajabi
- Department of Chemistry, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada A1N 4T8
| | - Elizabeth A. L. Gillis
- Department of Chemistry, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada A1N 4T8
| | - Travis D. Fridgen
- Department of Chemistry, Memorial University of Newfoundland, St. John’s, Newfoundland and Labrador, Canada A1N 4T8
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31
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Structure and vibrational assignment of the enol form of 1-chloro-1,1-difluoro-pentane-2,4-dione. J Mol Struct 2008. [DOI: 10.1016/j.molstruc.2007.07.040] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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33
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Szczepaniak K, Person WB, Hadzi D. Experimental matrix isolation study and quantum-mechanics-based normal-coordinate analysis of the anharmonic infrared spectrum of picolinic acid N-oxide. J Phys Chem A 2007; 109:6710-24. [PMID: 16834024 DOI: 10.1021/jp058089o] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
This work is, according to our knowledge, the first experimental matrix isolation study of a molecular system with a very short and strong intramolecular OH...O hydrogen bond. It also includes a satisfying interpretation of its entire infrared spectrum. The interpretation relies on the calculation at the DFT/B3LYP/6-31G(d,p) level of the harmonic spectrum and of the anharmonic relaxed potential energy for the stretching motion of the hydrogen-bonded proton, used with our recently modified quantum-mechanics-based normal-coordinate analysis. An important observation about the anharmonic spectrum obtained from this procedure is that the OH stretch coordinate contributes to several normal modes, mixing extensively with other in-plane internal coordinates, in particular OH-bending and C=O-stretching. The two intense normal modes with the largest contributions from the OH-stretching coordinate to the potential energy distribution and to the intensity are located near 1700 and 1500 cm(-1). A calculated anharmonic spectrum obtained from this procedure agrees with the experimental spectrum (frequencies and intensity distribution), within the limits of the estimated uncertainties for the calculation and experiment, allowing the interpretation of the latter. The agreement for the frequencies is about 1-3%. The anharmonic spectrum calculated using the anharmonic keyword in Gaussian 03w is not in satisfactory agreement with experiment insofar as the OH-stretching mode is concerned.
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Affiliation(s)
- Krystyna Szczepaniak
- Department of Chemistry, University of Florida, P O Box 117200, Gainesville, Florida 32611, USA
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34
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Tew DP, Handy NC, Carter S. A reaction surface Hamiltonian study of malonaldehyde. J Chem Phys 2007; 125:084313. [PMID: 16965018 DOI: 10.1063/1.2338891] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We report calculations using a reaction surface Hamiltonian for which the vibrations of a molecule are represented by 3N-8 normal coordinates, Q, and two large amplitude motions, s(1) and s(2). The exact form of the kinetic energy operator is derived in these coordinates. The potential surface is first represented as a quadratic in Q, the coefficients of which depend upon the values of s(1),s(2) and then extended to include up to Q(6) diagonal anharmonic terms. The vibrational energy levels are evaluated by solving the variational secular equations, using a basis of products of Hermite polynomials and appropriate functions of s(1),s(2). Our selected example is malonaldehyde (N=9) and we choose as surface parameters two OH distances of the migrating H in the internal hydrogen transfer. The reaction surface Hamiltonian is ideally suited to the study of the kind of tunneling dynamics present in malonaldehyde. Our results are in good agreement with previous calculations of the zero point tunneling splitting and in general agreement with observed data. Interpretation of our two-dimensional reaction surface states suggests that the OH stretching fundamental is incorrectly assigned in the infrared spectrum. This mode appears at a much lower frequency in our calculations due to substantial transition state character.
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Affiliation(s)
- David P Tew
- Institut für Physikalische Chemie, Universität Karlsruhe (TH), D-76128 Karlsruhe, Germany.
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35
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Ośmiałowski B, Raczyńska ED, Krygowski TM. Tautomeric equilibria and pi electron delocalization for some monohydroxyarenes--quantum chemical studies. J Org Chem 2007; 71:3727-36. [PMID: 16674042 DOI: 10.1021/jo052615q] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Keto-enol tautomeric interconversions and variations of the pi-electron distribution were studied for 11 isolated monohydroxyarenes at the DFT(B3LYP)/6-311++G(2df,2p) level. For two monohydroxyarenes (phenol and 9-anthrol), the PCM model of solvation (water) was also applied to the DFT geometries. The geometry-based HOMA index was applied to estimate pi-electron delocalization in the keto and enol tautomeric forms. Thermodynamic parameters of tautomeric interconversions (DeltaET, DeltaGT, TDeltaST, pKT) were calculated to estimate relative stabilities of individual tautomers and their percentage contents in the tautomeric mixtures. In almost all cases, the aromatic enol forms are strongly favored. An exception is 9-anthrol, which prefers its keto form. The resonance stabilization of this form comes from the central ring. Generally, aromaticity is the main factor that influences tautomeric equilibria in monohydroxyarenes. Hydration effect is considerably smaller and it does not change the tautomeric preference.
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Affiliation(s)
- Borys Ośmiałowski
- Department of Chemistry, Technical and Agricultural University, ul. Seminaryjna 3, 85-326 Bydgoszcz, Poland
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36
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Karavas E, Georgarakis E, Sigalas MP, Avgoustakis K, Bikiaris D. Investigation of the release mechanism of a sparingly water-soluble drug from solid dispersions in hydrophilic carriers based on physical state of drug, particle size distribution and drug–polymer interactions. Eur J Pharm Biopharm 2007; 66:334-47. [PMID: 17267194 DOI: 10.1016/j.ejpb.2006.11.020] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2006] [Revised: 11/22/2006] [Accepted: 11/23/2006] [Indexed: 11/21/2022]
Abstract
In the present study the release mechanism of the sparingly water-soluble drug felodipine (FELO) from particulate solid dispersions in PVP or PEG was investigated. FT-IR data indicated that a N-H...O hydrogen bond is formed between FELO and polymers. The drug-polymer interaction was theoretically studied with the density functional theory with the B3LYP exchange correlation function. The interaction energies have been estimated at -31.8 kJ/mol for PVP and -18.8 kJ/mol for PEG. Also, detailed vibrational analysis of the complexes showed that the red shift of the N-H bond stretching in FELO molecule due to H-bonding was higher in the FELO-PVP complex than in the FELO-PEG complex. Both the experimental and theoretical data indicated that a stronger interaction of FELO with PVP than with PEG was developed. The interactions of FELO with the polymer appeared to control the physical state (amorphous or crystalline) and the particle size of FELO in the solid dispersions. In the FELO/PVP dispersions, the drug is found as amorphous nanoparticles whereas in FELO/PEG dispersions the drug is dispersed as crystalline microparticles. The size of drug particles in the dispersion was also influenced by drug proportion, with an increase in drug content of the dispersion resulting in increased drug particle size. The particle size of drug, the proportion of drug in the dispersion and the properties of the polymer (molecular weight) appeared to determine the mechanism of drug release from the solid dispersions, which was drug diffusion (through the polymer layer)-controlled at low drug contents and drug dissolution-controlled at high drug contents. In situ DLS measurements indicate that the large initial particles of FELO/PVP and FELO/PEG solid dispersions with low drug content (10-20 wt%) are very rapidly decreased to smaller particles (including nanoparticles) during dissolution, leading to the observed impressive enhancement of FELO release rate from these dispersions.
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Trivella A, Roubin P, Theulé P, Rajzmann M, Coussan S, Manca C. UV and IR Photoisomerization of Acetylacetone Trapped in a Nitrogen Matrix. J Phys Chem A 2007; 111:3074-81. [PMID: 17394292 DOI: 10.1021/jp068763h] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
UV- and IR-induced photoisomerization of acetylacetone trapped in a nitrogen matrix at 4.3 K have been carried out using a tunable optical parametric oscillator type laser, or a mercury vapor lamp, coupled with Fourier Transform IR and UV spectroscopies. After deposition, the main form present in the cryogenic matrix is that chelated (enol). Upon UV irradiation, the intramolecular H bond is broken leading to nonchelated isomers among seven possible open forms. These forms have then been irradiated by resonant pi* <-- pi UV irradiation, or by resonant nuOH irradiation. The selective UV irradiation allows us to suggest a first vibrational assignment while the nuOH irradiation leads us to observe interconversions between the nonchelated isomers. In order to support our vibrational assignment, we have carried out theoretical calculations at the B3LYP/6-311++G(2d,2p) level of theory. This study shows that only five isomers are observed among eight postulated.
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Affiliation(s)
- A Trivella
- Laboratoire Physique des Interactions Ioniques et Moléculaires, UMR 6633, Université de Provence-CNRS, Centre St-Jérôme, 13397 Marseille Cedex 20, France
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Tayyari SF, Vakili M, Nekoei AR, Rahemi H, Wang YA. Vibrational assignment and structure of trifluorobenzoylacetone. A density functional theoretical study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 66:626-36. [PMID: 16860593 DOI: 10.1016/j.saa.2006.04.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Revised: 03/31/2006] [Accepted: 04/03/2006] [Indexed: 05/11/2023]
Abstract
Molecular structure and vibrational frequencies of 4,4,4-trifluoro-1-phenyl-1,3-butanedione, known as trifluorobenzoylacetone (TFBA), have been investigated by means of density functional theory (DFT) calculations. The results were compared with those of benzoylacetone (BA), acetylacetone (AA), and trifluoroacetylacetone (TFAA). Comparing the calculated and experimental band frequencies and intensities suggests coexisting of both stable cis-enol conformers in comparable proportions in the sample. The energy difference between the two stable chelated enol forms is negligible, 0.96 kcal/mol, calculated at B3LYP/6-311++G** level of theory. The molecular stability and the hydrogen bond strength were investigated by applying the natural bond orbital (NBO) theory and geometry calculations. The theoretical calculations and spectroscopic results indicate that the hydrogen bond strength of TFBA is between those of TFAA and AA, considerably weaker than that of BA.
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Tayyari SF, Zahedi-Tabrizi M, Laleh S, Moosavi-Tekyeh Z, Rahemi H, Wang YA. Structure and vibrational assignment of 3,4-diacetyl-2,5-hexanedione. A density functional theoretical study. J Mol Struct 2007. [DOI: 10.1016/j.molstruc.2006.05.028] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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40
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Tayyari SF, Rahemi H, Nekoei AR, Zahedi-Tabrizi M, Wang YA. Vibrational assignment and structure of dibenzoylmethane. A density functional theoretical study. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 66:394-404. [PMID: 16843716 DOI: 10.1016/j.saa.2006.03.010] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2006] [Revised: 03/01/2006] [Accepted: 03/02/2006] [Indexed: 05/10/2023]
Abstract
Molecular structure and vibrational frequencies of 1,3-diphenyl-1,3-propanedione, known as dibenzoylmethane (DBM), have been investigated by means of density functional theory (DFT) calculations. The results were compared with those of benzoylacetone (BA) and acetylacetone (AA), the parent molecule. IR and Raman spectra of DBM and its deuterated analogue were clearly assigned. The calculated hydrogen bond energy of DBM is 16.15 kcal/mol, calculated at B3LYP/6-311++G** level of theory, which is 0.28 kcal/mol more than that of AA. This result is in agreement with the vibrational and NMR spectroscopy results. The molecular stability and the hydrogen bond strength were investigated by applying the Natural Bond Orbital analysis (NBO) and geometry calculations. The theoretical calculations indicate that the hydrogen bond in DBM is relatively stronger than that in BA and AA.
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Affiliation(s)
- S F Tayyari
- Chemistry Department, Khayyam Higher Education, Mashhad 9189747178, Iran.
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41
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Theoretical study of hydrogen bond interactions of felodipine with polyvinylpyrrolidone and polyethyleneglycol. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/j.theochem.2006.09.016] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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42
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Zahedi-Tabrizi M, Tayyari F, Moosavi-Tekyeh Z, Jalali A, Tayyari SF. Structure and vibrational assignment of the enol form of 1,1,1-trifluoro-2,4-pentanedione. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2006; 65:387-96. [PMID: 16500140 DOI: 10.1016/j.saa.2005.11.019] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2005] [Revised: 11/14/2005] [Accepted: 11/14/2005] [Indexed: 05/06/2023]
Abstract
Molecular structure of 1,1,1-trifluoro-pentane-2,4-dione, known as trifluoro-acetylacetone (TFAA), has been investigated by means of Density Functional Theory (DFT) calculations and the results were compared with those of acetylacetone (AA) and hexafluoro-acetylacetone (HFAA). The harmonic vibrational frequencies of both stable cis-enol forms were calculated at B3LYP level of theory using 6-31G** and 6-311++G** basis sets. We also calculated the anharmonic frequencies at B3LYP/6-31G** level of theory for both stable cis-enol isomers. The calculated frequencies, Raman and IR intensities, and depolarization ratios were compared with the experimental results. The energy difference between the two stable cis-enol forms, calculated at B3LYP/6-311++G**, is only 5.89 kJ/mol. The observed vibrational frequencies and Raman and IR intensities are in excellent agreement with the corresponding values calculated for the most stable conformation, 2TFAA. According to the theoretical calculations, the hydrogen bond strength for the most stable conformer is 57 kJ/mol, about 9.5kJ/mol less than that of AA and about 14.5 kJ/mol more than that of HFAA. These hydrogen bond strengths are consistent with the frequency shifts for OH/OD stretching and OH/OD out-of-plane bending modes upon substitution of CH(3) groups with CF(3) groups. By comparing the vibrational spectra of both theoretical and experimental data, it was concluded that 2TFAA is the dominant isomer.
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Molecular structure and vibrational assignment of (trifluoroacetyl) acetone: A density functional study. J Mol Struct 2006. [DOI: 10.1016/j.molstruc.2005.10.042] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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45
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Coussan S, Ferro Y, Trivella A, Rajzmann M, Roubin P, Wieczorek R, Manca C, Piecuch P, Kowalski K, Włoch M, Kucharski SA, Musiał M. Experimental and Theoretical UV Characterizations of Acetylacetone and Its Isomers. J Phys Chem A 2006; 110:3920-6. [PMID: 16539413 DOI: 10.1021/jp056834r] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Cryogenic matrix isolation experiments have allowed the measurement of the UV absorption spectra of the high-energy non-chelated isomers of acetylacetone, these isomers being produced by UV irradiation of the stable chelated form. Their identification has been done by coupling selective UV-induced isomerization, infrared spectroscopy, and harmonic vibrational frequency calculations using density functional theory. The relative energies of the chelated and non-chelated forms of acetylacetone in the S0 state have been obtained using density functional theory and coupled-cluster methods. For each isomer of acetylacetone, we have calculated the UV transition energies and dipole oscillator strengths using the excited-state coupled-cluster methods, including EOMCCSD (equation-of-motion coupled-cluster method with singles and doubles) and CR-EOMCCSD(T) (the completely renormalized EOMCC approach with singles, doubles, and non-iterative triples). For dipole-allowed transition energies, there is a very good agreement between experiment and theory. In particular, the CR-EOMCCSD(T) approach explains the blue shift in the electronic spectrum due to the formation of the non-chelated species after the UV irradiation of the chelated form of acetylacetone. Both experiment and CR-EOMCCSD(T) theory identify two among the seven non-chelated forms to be characterized by red-shifted UV transitions relative to the remaining five non-chelated isomers.
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Affiliation(s)
- S Coussan
- Laboratoire Physique des Interactions Ioniques et Moléculaires, UMR 6633, Université de Provence-CNRS, Centre St-Jérôme, 13397 Marseille Cedex 20, France.
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Nowroozi A, Raissi H. Strong intramolecular hydrogen bond in triformylmethane ab-initio, AIM and NBO study. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.theochem.2005.10.037] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Aschi M, D'Abramo M, Ramondo F, Daidone I, D'Alessandro M, Di Nola A, Amadei A. Theoretical modeling of chemical reactions in complex environments: the intramolecular proton transfer in aqueous malonaldehyde. J PHYS ORG CHEM 2006. [DOI: 10.1002/poc.1051] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Wassermann TN, Luckhaus D, Coussan S, Suhm MA. Proton tunneling estimates for malonaldehyde vibrations from supersonic jet and matrix quenching experiments. Phys Chem Chem Phys 2006; 8:2344-8. [PMID: 16710482 DOI: 10.1039/b602319n] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
FTIR tunneling splittings for a range of fundamental excitations of malonaldehyde are determined from adiabatic cooling and symmetry breaking experiments in three different molecular states (isolated, coated by Ar layers and embedded in bulk Ar matrices), showing that there is room for improvement in available theoretical models.
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Affiliation(s)
- T N Wassermann
- Institut für Physikalische Chemie, Universität Göttingen, Germany.
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49
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Tayyari S, Moosavi-Tekyeh Z, Zahedi-Tabrizi M, Eshghi H, Emampour J, Rahemi H, Hassanpour M. Intramolecular hydrogen bonding in 2-nitromalonaldehyde: Infrared spectrum and quantum chemical calculations. J Mol Struct 2006. [DOI: 10.1016/j.molstruc.2005.08.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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50
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Meyer * R, Ha TK. Rotational constants of malonaldehyde and isotopic species derived fromab initioresults. Mol Phys 2005. [DOI: 10.1080/00268970500126199] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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