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Saxena A, Prasad D, Thakur KK, Kaur J. PDP, EIS, and Surface Studies of the Low-Carbon Steel by the Extract of Tinospora cordifolia: A Green Approach to the Corrosion Inhibition. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2020. [DOI: 10.1007/s13369-020-04894-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Electrochemical Studies and the Surface Examination of Low Carbon Steel by Applying the Extract of Citrus sinensis. ACTA ACUST UNITED AC 2020. [DOI: 10.1007/s40735-020-00338-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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3
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Yatsyna V, Bakker DJ, Feifel R, Rijs AM, Zhaunerchyk V. Aminophenol isomers unraveled by conformer-specific far-IR action spectroscopy. Phys Chem Chem Phys 2016; 18:6275-83. [DOI: 10.1039/c5cp07426f] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Far-infrared action spectroscopy of aminophenol in the gas-phase revealed isomer- and conformer-specific vibrational signatures and provided the heights of NH2 inversion barrier.
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Affiliation(s)
- Vasyl Yatsyna
- University of Gothenburg
- Department of Physics
- 412 96 Gotheburg
- Sweden
- Radboud University
| | - Daniël J. Bakker
- Radboud University
- Institute for Molecules and Materials
- FELIX Laboratory
- 6525 ED Nijmegen
- The Netherlands
| | - Raimund Feifel
- University of Gothenburg
- Department of Physics
- 412 96 Gotheburg
- Sweden
| | - Anouk M. Rijs
- Radboud University
- Institute for Molecules and Materials
- FELIX Laboratory
- 6525 ED Nijmegen
- The Netherlands
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Heid CG, Merrill WG, Case AS, Crim FF. Vibrational predissociation and vibrationally induced isomerization of 3-aminophenol-ammonia. J Chem Phys 2015; 142:014310. [PMID: 25573564 DOI: 10.1063/1.4904893] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We investigate the vibrational predissociation dynamics of the hydrogen-bonded 3-aminophenol-ammonia cluster (3-AP-NH3) in the OH and NH stretching regions. Vibrational excitation provides enough energy to dissociate the cluster into its constituent 3-AP and NH3 monomers, and we detect the 3-AP fragments via (1 + 1) resonance-enhanced multiphoton ionization (REMPI). The distribution of vibrational states of the 3-AP fragment suggests the presence of two distinct dissociation pathways. The first dissociation channel produces a broad, unstructured feature in the REMPI-action spectrum after excitation of any of the OH or NH stretching vibrations, pointing to a nearly statistical dissociation pathway with extensive coupling among the vibrations in the cluster during the vibrational predissociation. The second dissociation channel produces distinct, resolved features on top of the broad feature but only following excitation of the OH or symmetric NH3 stretch in the cluster. This striking mode-specificity is consistent with strong coupling of these two modes to the dissociation coordinate (the O-H⋯N bond). The presence of clearly resolved transitions to the electronic origin and to the 10a(2) + 10b(2) state of the cis-3-AP isomer shows that vibrational excitation is driving the isomerization of the trans-3-AP-NH3 isomer to the cis-3-AP-NH3 isomer in the course of the dissociation.
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Affiliation(s)
- Cornelia G Heid
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Wyatt G Merrill
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Amanda S Case
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - F Fleming Crim
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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Karsili TNV, Wenge AM, Harris SJ, Murdock D, Harvey JN, Dixon RN, Ashfold MNR. O–H bond fission in 4-substituted phenols: S1 state predissociation viewed in a Hammett-like framework. Chem Sci 2013. [DOI: 10.1039/c3sc50296a] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Zhang L, Muchall HM, Peslherbe GH. Substituent effects in the absorption spectra of phenol radical species: origin of the redshift caused by 3,5-dimethoxyl substitution. Photochem Photobiol 2012; 89:536-44. [PMID: 23216064 DOI: 10.1111/php.12028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Accepted: 11/07/2012] [Indexed: 12/31/2022]
Abstract
The ground-state equilibrium geometries, electronic structures and vertical excitation energies of methyl- and methoxyl-substituted phenol radical cations and phenoxyl radicals have been investigated using time-dependent density-functional theory (namely TD-B3LYP) and complete-active-space second-order perturbation theory (CASPT2). The "anomalous" large redshifts of the absorption maxima of the phenol radical species observed in the ultraviolet-visible spectral region upon di-meta-methoxyl substitution are reproduced by the calculations. Furthermore, these "anomalous" shifts which were unexplained to date can be rationalized on the basis of a qualitative molecular orbital perturbation analysis.
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Affiliation(s)
- Lei Zhang
- Centre for Research in Molecular Modeling and Department of Chemistry and Biochemistry, Concordia University, Montreal, QC, Canada
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Filsinger F, Meijer G, Stapelfeldt H, Chapman HN, Küpper J. State- and conformer-selected beams of aligned and oriented molecules for ultrafast diffraction studies. Phys Chem Chem Phys 2010; 13:2076-87. [PMID: 21165481 DOI: 10.1039/c0cp01585g] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The manipulation of the motion of neutral molecules with electric or magnetic fields has seen tremendous progress over the last decade. Recently, these techniques have been extended to the manipulation of large and complex molecules. In this article we introduce experimental approaches to the manipulation of large molecules, i.e., the deflection, focusing and deceleration using electric fields. We detail how these methods can be exploited to spatially separate quantum states and how to select individual conformers of complex molecules. We briefly describe mixed-field orientation experiments made possible by the quantum-state selection. Moreover, we provide an outlook on ultrafast diffraction experiments using these highly controlled samples.
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Affiliation(s)
- Frank Filsinger
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
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8
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Pure Samples of Individual Conformers: The Separation of Stereoisomers of Complex Molecules Using Electric Fields. Angew Chem Int Ed Engl 2009; 48:6900-2. [DOI: 10.1002/anie.200902650] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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9
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Filsinger F, Küpper J, Meijer G, Hansen J, Maurer J, Nielsen J, Holmegaard L, Stapelfeldt H. Reine Proben einzelner Konformere: die Trennung von Stereoisomeren komplexer Moleküle mittels elektrischer Felder. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200902650] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kostko O, Kim SK, Leone SR, Ahmed M. Mass-Analyzed Threshold Ionization (MATI) Spectroscopy of Atoms and Molecules Using VUV Synchrotron Radiation. J Phys Chem A 2009; 113:14206-11. [DOI: 10.1021/jp9008338] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Oleg Kostko
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, and Department of Chemistry and Physics, University of California at Berkeley, Berkeley, California 94720
| | - Sang Kyu Kim
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, and Department of Chemistry and Physics, University of California at Berkeley, Berkeley, California 94720
| | - Stephen R. Leone
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, and Department of Chemistry and Physics, University of California at Berkeley, Berkeley, California 94720
| | - Musahid Ahmed
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, and Department of Chemistry and Physics, University of California at Berkeley, Berkeley, California 94720
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Filsinger F, Wohlfart K, Schnell M, Grabow JU, Küpper J. Precise dipole moments and quadrupole coupling constants of the cis and trans conformers of 3-aminophenol: determination of the absolute conformation. Phys Chem Chem Phys 2008; 10:666-73. [DOI: 10.1039/b711888k] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Huang J, Huang K, Liu S, Luo Q, Tzeng W. Vibrational spectra and theoretical calculations of p-chlorophenol in the electronically excited S1 and ionic ground D0 states. J Photochem Photobiol A Chem 2008. [DOI: 10.1016/j.jphotochem.2007.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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13
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Soliman UA, Hassan AM, Mohamed TA. Conformational stability, vibrational assignmenents, barriers to internal rotations and ab initio calculations of 2-aminophenol (d 0 and d3). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2007; 68:688-700. [PMID: 17376737 DOI: 10.1016/j.saa.2006.12.047] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2006] [Revised: 12/26/2006] [Accepted: 12/31/2006] [Indexed: 05/14/2023]
Abstract
The Raman (3700-100 cm(-1)) and infrared (4000-400 cm(-1)) spectra of solid 2-aminophenol (2AP) have been recorded. The internal rotation of both OH and NH2 moieties produce ten conformers with either Cs or C1 symmetry. However, the calculated energies as well as the imaginary vibrational frequencies reduce rotational isomerism to five isomers. The molecular geometry has been optimized without any constraints using RHF, MP2 and B3LYP levels of theory at 6-31G(d), 6-311+G(d) and 6-31++G(d,p) basis sets. All calculations predict 1 (cis; OH is directed towards NH2) to be the most stable conformation except RHF/6-31++G(d,p) basis set. The 1 (cis) isomer is found to be more stable than 8 (trans; OH is away from the NH2 moiety and the NH bonds are out-of-plane) by 1.7 kcal/mol (598 cm(-1)) as obtained from MP2/6-31G(d) calculations. Aided by experimental and theoretical vibrational spectra, cis and trans 2AP are coexist in solution but cis isomer is more likely present in the crystalline state. Aided by MP2 and B3LYP frequency calculations, molecular force fields, simulated vibrational spectra utilizing 6-31G(d) basis set as well as normal coordinate analysis, complete vibrational assignments for HOC6H4NH2 and DOC6H4ND2 have been proposed. Furthermore, we carried out potential surface scan, to determine the barriers to internal rotations of NH2 and OH groups. All results are reported herein and compared with similar molecules when appropriate.
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Affiliation(s)
- Usama A Soliman
- Department of Chemistry, Faculty of Science (Boys), Al-Azhar University, Nasr City 11884, Cairo, Egypt
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Gerhards M, Jansen A, Unterberg C, Gerlach A. Structures and rearrangement reactions of 4-aminophenol(H2O)1+ and 3-aminophenol(H2O)1+ clusters. J Chem Phys 2005; 123:074320. [PMID: 16229583 DOI: 10.1063/1.2008255] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
In this paper the structures of 4-aminophenol(H2O)1+ and 3-aminophenol(H2O)1+ clusters are investigated in molecular beam experiments by different IR/UV-double resonance techniques as well as the mass analyzed threshold ionization spectroscopy yielding both inter- and intramolecular vibrations of the ionic and neutral species. Possible structures are extensively calculated at the level of density functional theory (DFT) or at the ab initio level of theory. From the experimental and theoretical investigations it can be concluded that in the case of 4-aminophenol(H2O)1 one O-H...O hydrogen-bonded structure exists in the neutral cluster but two structures containing either an O-H...O or a N-H...O hydrogen-bonded arrangement are observed in the spectra of the ionic species. This observation is a result of an intramolecular rearrangement reaction within the ion which can only take place if high excess energies are used. A reaction path via the CH bonds is calculated and explains the experimental observations. In the case of 3-aminophenol(H2O)1+ only one O-H...O bound structure is observed both in the neutral and ionic species. Ab initio and DFT calculations show that due to geometrical and energetical reasons a rearrangement cannot be observed in the 3-aminophenol(H2O)1+ cluster ion.
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Affiliation(s)
- M Gerhards
- Heinrich-Heine-Universität Düsseldorf, Institut für Physikalische Chemie I, 40225 Düsseldorf, Germany.
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Li C, Pradhan M, Tzeng WB. Mass analyzed threshold ionization spectroscopy of p-cyanophenol cation and the CN substitution effect. Chem Phys Lett 2005. [DOI: 10.1016/j.cplett.2005.06.085] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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