1
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Kostin MA, Alkhuder O, Xu L, Krutin DV, Asfin RE, Tolstoy PM. Complexes of phosphine oxides with substituted phenols: hydrogen bond characterization based on shifts of PO stretching bands. Phys Chem Chem Phys 2024; 26:10234-10242. [PMID: 38497315 DOI: 10.1039/d3cp05817d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
In this work IR spectral characteristics of PO groups are used to evaluate the strength of OHO hydrogen bonds. Three phosphine oxides: triphenylphosphine oxide, tributylphosphine oxide and hexamethylphosphoramide are investigated as proton acceptors. The results of the experimental IR study and DFT calculation of 30 complexes formed by phosphine oxides with various substituted phenols or CF3CH2OH in CCl4 solution at room temperature are reported. We show that the PO vibrational frequency changes non-linearly upon hydrogen bond formation and strengthening and that the shift of the PO band could be used for the estimation of hydrogen bond strength in complexes with phosphine oxides. The accuracy of these estimations and the influence of solvation effects on the main characteristics of complexes are discussed.
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Affiliation(s)
- Mikhail A Kostin
- Institute of Chemistry, St. Petersburg State University, St. Petersburg, Russia.
| | - Omar Alkhuder
- Institute of Chemistry, St. Petersburg State University, St. Petersburg, Russia.
| | - Luhang Xu
- Department of Physics, St. Petersburg State University, St. Petersburg, Russia.
| | - Danil V Krutin
- Institute of Chemistry, St. Petersburg State University, St. Petersburg, Russia.
| | - Ruslan E Asfin
- Department of Physics, St. Petersburg State University, St. Petersburg, Russia.
| | - Peter M Tolstoy
- Institute of Chemistry, St. Petersburg State University, St. Petersburg, Russia.
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2
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Ali S, Akhter MS, Waqas M, Zubair H, Bhatti HN, Mahal A, Shawky AM, Alkhouri A, Khera RA. End-capped engineering of Quinoxaline core-based non-fullerene acceptor materials with improved power conversion efficiency. J Mol Graph Model 2024; 127:108699. [PMID: 38150839 DOI: 10.1016/j.jmgm.2023.108699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 12/17/2023] [Accepted: 12/19/2023] [Indexed: 12/29/2023]
Abstract
Improving the light-harvesting efficiency and boosting open circuit voltage are crucial challenges for enhancing the efficiency of organic solar cells. This work introduces seven new molecules (SA1-SA7) to upgrade the optoelectronic and photovoltaic properties of Q-C-F molecule-based solar cells. All recently designed molecules have the same alkyl-substituted Quinoxaline core and CPDT donor but vary in the end-capped acceptor subunits. All the investigated molecules have revealed superior properties than the model (R) by having absorbance ranging from 681 nm to 782 nm in the gaseous medium while 726 nm-861 nm in chloroform solvent, with the lowest band gap ranging from 1.91 to 2.19 eV SA1 molecule demonstrated the highest λmax (861 nm) in chloroform solvent and the lowest band gap (1.91 eV). SA2 molecule has manifested highest dipole moment (4.5089 D), lower exciton binding energy in gaseous (0.33 eV) and chloroform solvent (0.47 eV), and lower charge mobility of hole (0.0077693) and electron (0.0042470). At the same time, SA7 showed the highest open circuit voltage (1.56 eV) and fill factor (0.9166) due to solid electron-pulling acceptor moieties. From these supportive outcomes, it is inferred that our computationally investigated molecules may be promising candidates to be used in advanced versions of OSCs in the upcoming period.
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Affiliation(s)
- Sajjad Ali
- Department of Chemistry, University of Agriculture, Faisalabad, 38000, Pakistan
| | - Muhammad Salim Akhter
- Department of Chemistry, College of Science, University of Bahrain, P. O. Box 32028, Bahrain
| | - Muhammad Waqas
- Department of Chemistry, University of Agriculture, Faisalabad, 38000, Pakistan
| | - Hira Zubair
- Department of Chemistry, University of Agriculture, Faisalabad, 38000, Pakistan
| | - Haq Nawaz Bhatti
- Department of Chemistry, University of Agriculture, Faisalabad, 38000, Pakistan
| | - Ahmed Mahal
- Department of Medical Biochemical Analysis, College of Health Technology, Cihan University-Erbil, Erbil, Kurdistan Region, Iraq
| | - Ahmed M Shawky
- Science and Technology Unit (STU), Umm Al-Qura University, Makkah, 21955, Saudi Arabia
| | - Anas Alkhouri
- College of Pharmacy, Cihan University-Erbil, Erbil, Kurdistan Region, Iraq
| | - Rasheed Ahmad Khera
- Department of Chemistry, University of Agriculture, Faisalabad, 38000, Pakistan.
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3
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Hack JH, Chen Y, Lewis NHC, Kung HH, Tokmakoff A. Strong H-bonding from Zeolite Bro̷nsted Acid Site to Water: Origin of the Broad IR Doublet. J Phys Chem B 2023; 127:11054-11063. [PMID: 38109274 DOI: 10.1021/acs.jpcb.3c06819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
Hydrogen bonding between water molecules and zeolite Bro̷nsted acid sites (BAS) has received much attention due to the significant influence of water on the adsorption and catalytic properties of these widely used porous materials. When a single water molecule is adsorbed at the BAS, the zeolite O-H stretch vibration decreases in frequency and splits into two extraordinarily broad bands peaked near 2500 and 2900 cm-1 in the infrared (IR) spectrum. This broad doublet feature is the predominant IR signature used to identify and interpret water-BAS H-bonding at low hydration levels, but the origin of the band splitting is not well understood. In this study, we used broadband two-dimensional infrared (2D IR) spectroscopy to investigate zeolite HZSM-5 prepared with a single water molecule per BAS. We find that the 2D IR spectrum is not explained by the most common interpretation of Fermi resonance coupling between the stretch and the bend of the BAS OH group, which predicts intense excited-state transitions that are absent from the experimental results. We present an alternative model of a double-well proton stretch potential, where the band splitting is caused by excited-state tunneling through the proton-transfer barrier. This one-dimensional model reproduces the basic experimental pattern of transition frequencies and amplitudes, suggesting that the doublet bands may originate from a highly anharmonic potential in which the excited state proton wave functions are delocalized over the H-bond between zeolite BAS and adsorbed H2O. Additional details about molecular orientation and coordination of the adsorbed water molecule are also resolved in the 2D IR spectroscopy.
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Affiliation(s)
- John H Hack
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States
| | - Yaxin Chen
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Nicholas H C Lewis
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States
| | - Harold H Kung
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
| | - Andrei Tokmakoff
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, United States
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4
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Dean JLS, Winkler VS, Boyer MA, Sibert EL, Fournier JA. Investigating Intramolecular H Atom Transfer Dynamics in β-Diketones with Ultrafast Infrared Spectroscopies and Theoretical Modeling. J Phys Chem A 2023; 127:9258-9272. [PMID: 37882618 DOI: 10.1021/acs.jpca.3c05417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
The vibrational signatures and ultrafast dynamics of the intramolecular H-bond in a series of β-diketones are investigated with 2D IR spectroscopy and computational modeling. The chosen β-diketones exhibit a range of H atom donor-acceptor distances and asymmetry along the H atom transfer coordinate that tunes the intramolecular H-bond strength. The species with the strongest H-bonds are calculated to have very soft H atom potentials, resulting in highly red-shifted OH stretch fundamental frequencies and dislocation of the H atom upon vibrational excitation. These soft potentials lead to significant coupling to the other normal mode coordinates and give rise to the very broad vibrational signatures observed experimentally. The 2D IR spectra in both the OH and OD stretch regions of the light and deuterated isotopologues reveal broadened and long-lived ground-state bleach signatures of the vibrationally hot molecules. Polarization-sensitive transient absorption measurements in the OH and OD stretch regions reveal notable isotopic differences in orientational dynamics. Orientational relaxation was measured to occur on ∼600 fs and ∼2 ps time scales for the light and deuterated isotopologues, respectively. The orientational dynamics are interpreted in terms of activated H/D atom transfer events driven by collective intramolecular structural rearrangements.
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Affiliation(s)
- Jessika L S Dean
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Valerie S Winkler
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Mark A Boyer
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin Madison, Madison, Wisconsin 53706, United States
| | - Edwin L Sibert
- Department of Chemistry and Theoretical Chemistry Institute, University of Wisconsin Madison, Madison, Wisconsin 53706, United States
| | - Joseph A Fournier
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
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5
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Dean JLS, Fournier JA. Vibrational Dynamics of the Intramolecular H-Bond in Acetylacetone Investigated with Transient and 2D IR Spectroscopy. J Phys Chem B 2022; 126:3551-3562. [PMID: 35536173 DOI: 10.1021/acs.jpcb.2c00793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Acetylacetone (AcAc) has proven to be a fruitful but highly challenging model system for the experimental and computational interrogation of strong intramolecular hydrogen bonds. Key questions remain, however, regarding the identity of the minimum-energy structure of AcAc and the dynamics of intramolecular proton transfer. Here, we investigate the OH/OD stretch and bend regions of the enol tautomer of AcAc and its deuterated isotopologue with transient absorption and 2D IR spectroscopy. The OH bend region reveals a single dominant diagonal transition near 1625 cm-1 with intense cross peaks to lower-frequency modes, demonstrating highly mixed fingerprint transitions that contain OH bend character. The anharmonic coupling of the OH bend results in a highly elongated OH bend excited-state absorption transition that indicates a large manifold of OH bend overtone/combination bands in the OH stretch region that leads to strong bend-stretch Fermi resonance interactions. The OH and OD stretch regions consist of broad ground-state bleach signals, but there is no clear evidence of ω21 excited-state absorptions due to rapid population relaxation arising from strong intramolecular coupling to bending, fingerprint, and low-frequency H-bond modes. Orientational relaxation dynamics persist for timescales longer than the vibrational lifetimes, with polarization anisotropy components decaying within approximately 2 and 10 periods of the O-O oscillation for the OH and OD stretch, respectively. The significant isotopic dependence of the orientational dynamics is discussed in the context of intramolecular mode coupling, diffusional processes, and contributions from proton/deuteron transfer dynamics.
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Affiliation(s)
- Jessika L S Dean
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri, United States 63130
| | - Joseph A Fournier
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri, United States 63130
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6
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Agarwal P, Nieuwoudt MK, Li S, Procter G, Andrews GP, Jones DS, Svirskis D. Exploiting Hydrogen Bonding to Enhance Lidocaine Loading and Stability in a Poly Ethylene-co-Vinyl acetate Carrier Matrix. Int J Pharm 2022; 621:121819. [DOI: 10.1016/j.ijpharm.2022.121819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/06/2022] [Accepted: 05/07/2022] [Indexed: 10/18/2022]
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7
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Chen L, Fournier JA. Probing Hydrogen-Bonding Interactions within Phenol-Benzimidazole Proton-Coupled Electron Transfer Model Complexes with Cryogenic Ion Vibrational Spectroscopy. J Phys Chem A 2021; 125:9288-9297. [PMID: 34652915 DOI: 10.1021/acs.jpca.1c05879] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Hydrogen-bonding interactions within a series of phenol-benzimidazole model proton-coupled electron transfer (PCET) dyad complexes are characterized using cryogenic ion vibrational spectroscopy. A highly red-shifted and surprisingly broad (>1000 cm-1) transition is observed in one of the models and assigned to the phenolic OH stretch strongly H-bonded to the N(3) benzimidazole atom. The breadth is attributed to a combination of anharmonic Fermi-resonance coupling between the OH stretch and background doorway states involving OH bending modes and strong coupling of the OH stretch frequency to structural deformations along the proton-transfer coordinate accessible at the vibrational zero-point level. The other models show unexpected protonation of the benzimidazole group upon electrospray ionization instead of at more basic remote amine/amide groups. This leads to the formation of HO-+HN(3) H-bond motifs that are much weaker than the OH-N(3) H-bond arrangement. H-bonding between the N(1)H+ benzimidazole group and the carbonyl on the tyrosine backbone is the stronger and preferred interaction in these complexes. The results show that conjugation effects, secondary H-bond interactions, and H-bond soft modes strongly influence the OH-N(3) interaction and highlight the importance of the direct monitoring of proton stretch transitions in characterizing the proton-transfer reaction coordinate in PCET systems.
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Affiliation(s)
- Liangyi Chen
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Joseph A Fournier
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, United States
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8
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Asfin RE. IR Spectra of Hydrogen-Bonded Complexes of Trifluoroacetic Acid with Acetone and Diethyl Ether in the Gas Phase. Interaction between CH and OH Stretching Vibrations. J Phys Chem A 2019; 123:3285-3292. [PMID: 30916959 DOI: 10.1021/acs.jpca.8b10215] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The spectra of complexes of trifluoroacetic acid (TFA) with acetone and diethyl ether (DEE) and their perdeuterated isotopologues were extracted from the spectra of the mixture of the compounds recorded at room temperature. The ν(OH) bands of the complexes with protiated and deuterated acetone notably differ from each other, whereas these ν(OH) bands are practically not affected by the deuteration of DEE. An assumption about the interaction of CH and OH groups in the (CH3)-C═O···HO fragment is made. According to density functional theory calculations, complexes of TFA with both acetone and DEE have a cyclic structure with one strong ═O···HO hydrogen bond and one weak CH···O═ bond. The structural, spectroscopic, and electronic properties indicate an essential role of weak bonds in the total complexation energy of the systems studied.
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Affiliation(s)
- Ruslan E Asfin
- Department of Physics , Saint Petersburg State University , 7/9 Universitetskaya Nab. , 199034 Saint Petersburg , Russian Federation
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9
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Grafton AB, Cheatum CM. Two-dimensional infrared study of the C D and C O stretching vibrations in strongly hydrogen-bonded complexes. Chem Phys 2018. [DOI: 10.1016/j.chemphys.2018.05.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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10
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Scutelnic V, Perez MAS, Marianski M, Warnke S, Gregor A, Rothlisberger U, Bowers MT, Baldauf C, von Helden G, Rizzo TR, Seo J. The Structure of the Protonated Serine Octamer. J Am Chem Soc 2018; 140:7554-7560. [DOI: 10.1021/jacs.8b02118] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Valeriu Scutelnic
- Laboratory of Molecular Physical Chemistry, Ecole Polytechnique Fédérale de Lausanne, Station 6, CH-1015 Lausanne, Switzerland
| | - Marta A. S. Perez
- Laboratory of Computational Chemistry and Biochemistry, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Mateusz Marianski
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Stephan Warnke
- Laboratory of Molecular Physical Chemistry, Ecole Polytechnique Fédérale de Lausanne, Station 6, CH-1015 Lausanne, Switzerland
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Aurelien Gregor
- Laboratory of Computational Chemistry and Biochemistry, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Ursula Rothlisberger
- Laboratory of Computational Chemistry and Biochemistry, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Michael T. Bowers
- Department of Chemistry and Biochemistry, University of California Santa Barbara, Santa Barbara, California 93106, United States
| | - Carsten Baldauf
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Gert von Helden
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Thomas R. Rizzo
- Laboratory of Molecular Physical Chemistry, Ecole Polytechnique Fédérale de Lausanne, Station 6, CH-1015 Lausanne, Switzerland
| | - Jongcheol Seo
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
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11
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Van Hoozen BL, Petersen PB. Vibrational tug-of-war: The pKAdependence of the broad vibrational features of strongly hydrogen-bonded carboxylic acids. J Chem Phys 2018; 148:134309. [PMID: 29626887 DOI: 10.1063/1.5026675] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Brian L. Van Hoozen
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
| | - Poul B. Petersen
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
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12
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Stingel AM, Petersen PB. Interpreting Quasi-Thermal Effects in Ultrafast Spectroscopy of Hydrogen-Bonded Systems. J Phys Chem A 2018; 122:2670-2676. [PMID: 29466009 DOI: 10.1021/acs.jpca.7b12372] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Vibrational excitation of molecules in the condensed phase relaxes through vibrational modes of decreasing energy to ultimately generate an equilibrium state in which the energy is distributed among low-frequency modes. In ultrafast vibrational spectroscopy, changes in the vibrational features of hydrogen-bonded NH and OH stretch modes are typically observed to persist long after these high-frequency vibrations have relaxed. Due to the resemblance to the spectral changes caused by heating the sample, these features are typically described as arising from a hot ground state. However, these spectral features appear on ultrafast time scales that are much too fast to result from a true thermal state, and significant differences between the thermal difference spectrum and the induced quasi-thermal changes in ultrafast spectroscopy are often observed. Here, we examine and directly compare the thermal and quasi-thermal responses of the hydrogen-bonded homodimer of 7-azaindole with temperature-dependent FTIR spectroscopy and ultrafast mid-IR continuum spectroscopy. We find that the thermal difference spectra contain contributions from both dissociation of the hydrogen bonds and from frequency shifts due to changes in the thermal population of low-frequency modes. The transient spectra in ultrafast vibrational spectroscopy are also found to contain two contributions: initial frequency shifts over 2.3 ± 0.11 ps associated with equilibration of the initial excitation, and frequency shifts associated with the excitation of several fingerprint modes, which decay over 21.8 ± 0.11 ps, giving rise to a quasi-thermal response caused by a distribution of fingerprint modes being excited within the sample ensemble. This resembles the thermal frequency shifts due to population changes of low-frequency modes, but not the overall thermal spectrum, which is dominated by features caused by dimer dissociation. These findings provide insight into the changes in the vibrational spectrum from different origins and are important for assigning, analyzing, and comparing features in thermal and ultrafast vibrational spectroscopy of hydrogen-bonded complexes.
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Affiliation(s)
- Ashley M Stingel
- Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States
| | - Poul B Petersen
- Department of Chemistry and Chemical Biology , Cornell University , Ithaca , New York 14853 , United States
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13
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Van Hoozen BL, Petersen PB. A combined electronic structure and molecular dynamics approach to computing the OH vibrational feature of strongly hydrogen-bonded carboxylic acids. J Chem Phys 2017; 147:224304. [DOI: 10.1063/1.5000341] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Brian L. Van Hoozen
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
| | - Poul B. Petersen
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
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14
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Daly CA, Streacker LM, Sun Y, Pattenaude SR, Hassanali AA, Petersen PB, Corcelli SA, Ben-Amotz D. Decomposition of the Experimental Raman and Infrared Spectra of Acidic Water into Proton, Special Pair, and Counterion Contributions. J Phys Chem Lett 2017; 8:5246-5252. [PMID: 28976760 DOI: 10.1021/acs.jpclett.7b02435] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Textbooks describe excess protons in liquid water as hydronium (H3O+) ions, although their true structure remains lively debated. To address this question, we have combined Raman and infrared (IR) multivariate curve resolution spectroscopy with ab initio molecular dynamics and anharmonic vibrational spectroscopic calculations. Our results are used to resolve, for the first time, the vibrational spectra of hydrated protons and counterions and reveal that there is little ion-pairing below 2 M. Moreover, we find that isolated excess protons are strongly IR active and nearly Raman inactive (with vibrational frequencies of ∼1500 ± 500 cm-1), while flanking water OH vibrations are both IR and Raman active (with higher frequencies of ∼2500 ± 500 cm-1). The emerging picture is consistent with Georg Zundel's seminal work, as well as recent ultrafast dynamics studies, leading to the conclusion that protons in liquid water are primarily hydrated by two flanking water molecules, with a broad range of proton hydrogen bond lengths and asymmetries.
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Affiliation(s)
- Clyde A Daly
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Louis M Streacker
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
| | - Yuchen Sun
- Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Shannon R Pattenaude
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
| | - Ali A Hassanali
- Condensed Matter and Statistical Physics, International Centre for Theoretical Physics , Strada Costiera, 11, I-34151 Trieste, Italy
| | - Poul B Petersen
- Department of Chemistry and Chemical Biology, Cornell University , Ithaca, New York 14853, United States
| | - Steven A Corcelli
- Department of Chemistry and Biochemistry, University of Notre Dame , Notre Dame, Indiana 46556, United States
| | - Dor Ben-Amotz
- Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
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15
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Stingel AM, Petersen PB. Couplings Across the Vibrational Spectrum Caused by Strong Hydrogen Bonds: A Continuum 2D IR Study of the 7-Azaindole–Acetic Acid Heterodimer. J Phys Chem B 2016; 120:10768-10779. [DOI: 10.1021/acs.jpcb.6b05049] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Ashley M. Stingel
- Department
of Chemistry and
Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Poul B. Petersen
- Department
of Chemistry and
Chemical Biology, Cornell University, Ithaca, New York 14853, United States
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16
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Mandal A, Tokmakoff A. Vibrational dynamics of aqueous hydroxide solutions probed using broadband 2DIR spectroscopy. J Chem Phys 2016; 143:194501. [PMID: 26590536 DOI: 10.1063/1.4935174] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We employed ultrafast transient absorption and broadband 2DIR spectroscopy to study the vibrational dynamics of aqueous hydroxide solutions by exciting the O-H stretch vibrations of the strongly hydrogen-bonded hydroxide solvation shell water and probing the continuum absorption of the solvated ion between 1500 and 3800 cm(-1). We observe rapid vibrational relaxation processes on 150-250 fs time scales across the entire probed spectral region as well as slower vibrational dynamics on 1-2 ps time scales. Furthermore, the O-H stretch excitation loses its frequency memory in 180 fs, and vibrational energy exchange between bulk-like water vibrations and hydroxide-associated water vibrations occurs in ∼200 fs. The fast dynamics in this system originate in strong nonlinear coupling between intra- and intermolecular vibrations and are explained in terms of non-adiabatic vibrational relaxation. These measurements indicate that the vibrational dynamics of the aqueous hydroxide complex are faster than the time scales reported for long-range transport of protons in aqueous hydroxide solutions.
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Affiliation(s)
- Aritra Mandal
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, University of Chicago, Chicago, Illinois 60637, USA
| | - Andrei Tokmakoff
- Department of Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, University of Chicago, Chicago, Illinois 60637, USA
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17
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Wolke CT, DeBlase AF, Leavitt CM, McCoy AB, Johnson MA. Diffuse Vibrational Signature of a Single Proton Embedded in the Oxalate Scaffold, HO2CCO2(-). J Phys Chem A 2015; 119:13018-24. [PMID: 26608571 DOI: 10.1021/acs.jpca.5b10649] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To understand how the D2d oxalate scaffold (C2O4)(2-) distorts upon capture of a proton, we report the vibrational spectra of the cryogenically cooled HO2CCO2(-) anion and its deuterated isotopologue DO2CCO2(-). The transitions associated with the skeletal vibrations and OH bending modes are sharp and are well described by inclusion of cubic terms in the normal mode expansion of the potential surface through an extended Fermi resonance analysis. The ground state structure features a five-membered ring with an asymmetric intramolecular proton bond. The spectral signatures of the hydrogen stretches, on the contrary, are surprisingly diffuse, and this behavior is not anticipated by the extended Fermi scheme. We trace the diffuse bands to very strong couplings between the high-frequency OH-stretch and the low-frequency COH bends as well as heavy particle skeletal deformations. A simple vibrationally adiabatic model recovers this breadth of oscillator strength as a 0 K analogue of the motional broadening commonly used to explain the diffuse spectra of H-bonded systems at elevated temperatures, but where these displacements arise from the configurations present at the vibrational zero-point level.
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Affiliation(s)
- Conrad T Wolke
- Sterling Chemistry Laboratory, Yale University , New Haven, Connecticut 06520, United States
| | - Andrew F DeBlase
- Sterling Chemistry Laboratory, Yale University , New Haven, Connecticut 06520, United States.,Department of Chemistry, Purdue University , West Lafayette, Indiana 47907, United States
| | - Christopher M Leavitt
- Sterling Chemistry Laboratory, Yale University , New Haven, Connecticut 06520, United States
| | - Anne B McCoy
- Department of Chemistry, University of Washington , Seattle, Washington 98195, United States
| | - Mark A Johnson
- Sterling Chemistry Laboratory, Yale University , New Haven, Connecticut 06520, United States
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18
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Van Hoozen BL, Petersen PB. Origin of the Hadži ABC structure: An ab initio study. J Chem Phys 2015; 143:184305. [DOI: 10.1063/1.4935062] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Brian L. Van Hoozen
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
| | - Poul B. Petersen
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA
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Li JW, Morita M, Takahashi K, Kuo JL. Features in Vibrational Spectra Induced by Ar-Tagging for H3O+Arm, m = 0–3. J Phys Chem A 2015; 119:10887-92. [DOI: 10.1021/acs.jpca.5b08898] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jheng-Wei Li
- Institute
of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
- Department
of Physics, National Taiwan University, Taipei 10617, Taiwan
| | - Masato Morita
- Institute
of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Kaito Takahashi
- Institute
of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Jer-Lai Kuo
- Institute
of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
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