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Shimizu M, Shirota H. Intermolecular Dynamics of Positively and Negatively Charged Aromatics and Their Isoelectronic Neutral Analogs in Aqueous Solutions. J Phys Chem B 2022; 126:4309-4323. [PMID: 35658126 DOI: 10.1021/acs.jpcb.2c01517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, we investigated the temperature dependence of intermolecular vibrations and orientational dynamics in the aqueous solutions of imidazole hydrochloride, imidazole, sodium triazolide, and triazole using femtosecond Raman-induced Kerr effect spectroscopy (fs-RIKES) and steady-state Raman spectroscopy. The difference low-frequency Raman spectra under 250 cm-1 of the aqueous solutions relative to the neat water showed that the spectral shoulder in the high-frequency region at 60-100 cm-1, assigned to the libration of an aromatic ring, was higher in frequency for the imidazolium cation but lower for the triazolide anion than those of the respective neutral aromatics. The results of the ab initio quantum chemistry calculations of the clusters of the aromatics and water molecule(s) were consistent with the experimental spectra of the aqueous solutions. Further, the results of the temperature-dependent experiments showed that the signal intensity in the low-frequency region below 50 cm-1 increased for all solutions with an increase in temperature. In contrast, the spectral density in the high-frequency region above 80 cm-1 exhibited almost no shift for the 1.0 M solutions, while a significant red shift was observed for the 5.0 M solutions. In addition, the temperature-dependent densities, viscosities, and surface tensions were characterized for the aqueous aromatic solutions from 293 to 353 K.
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Affiliation(s)
- Masako Shimizu
- Department of Chemistry, Chiba University 1-33 Yayoi, Inage-ku, Chiba 263-8522, Japan
| | - Hideaki Shirota
- Department of Chemistry, Chiba University 1-33 Yayoi, Inage-ku, Chiba 263-8522, Japan
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2
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Ki H, Choi S, Kim J, Choi EH, Lee S, Lee Y, Yoon K, Ahn CW, Ahn DS, Lee JH, Park J, Eom I, Kim M, Chun SH, Kim J, Ihee H, Kim J. Optical Kerr Effect of Liquid Acetonitrile Probed by Femtosecond Time-Resolved X-ray Liquidography. J Am Chem Soc 2021; 143:14261-14273. [PMID: 34455778 DOI: 10.1021/jacs.1c06088] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Optical Kerr effect (OKE) spectroscopy is a method that measures the time-dependent change of the birefringence induced by an optical laser pulse using another optical laser pulse and has been used often to study the ultrafast dynamics of molecular liquids. Here we demonstrate an alternative method, femtosecond time-resolved X-ray liquidography (fs-TRXL), where the microscopic structural motions related to the OKE response can be monitored using a different type of probe, i.e., X-ray solution scattering. By applying fs-TRXL to acetonitrile and a dye solution in acetonitrile, we demonstrate that different types of molecular motions around photoaligned molecules can be resolved selectively, even without any theoretical modeling, based on the anisotropy of two-dimensional scattering patterns and extra structural information contained in the q-space scattering data. Specifically, the dynamics of reorientational (libration and orientational diffusion) and translational (interaction-induced motion) motions are captured separately by anisotropic and isotropic scattering signals, respectively. Furthermore, the two different types of reorientational motions are distinguished from each other by their own characteristic scattering patterns and time scales. The measured time-resolved scattering signals are in excellent agreement with the simulated scattering signals based on a molecular dynamics simulation for plausible molecular configurations, providing the detailed structural description of the OKE response in liquid acetonitrile.
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Affiliation(s)
- Hosung Ki
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Seungjoo Choi
- Department of Chemistry, Inha University, 100 Inha-ro, Michuhol-gu, Incheon 22212, Republic of Korea
| | - Jungmin Kim
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Eun Hyuk Choi
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Seonggon Lee
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Yunbeom Lee
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Kihwan Yoon
- Department of Chemistry, The Catholic University of Korea, Bucheon 14662, Republic of Korea
| | - Chi Woo Ahn
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Doo-Sik Ahn
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Jae Hyuk Lee
- Pohang Accelerator Laboratory, Pohang 37673, Republic of Korea
| | - Jaeku Park
- Pohang Accelerator Laboratory, Pohang 37673, Republic of Korea
| | - Intae Eom
- Pohang Accelerator Laboratory, Pohang 37673, Republic of Korea
| | - Minseok Kim
- Pohang Accelerator Laboratory, Pohang 37673, Republic of Korea
| | - Sae Hwan Chun
- Pohang Accelerator Laboratory, Pohang 37673, Republic of Korea
| | - Joonghan Kim
- Department of Chemistry, The Catholic University of Korea, Bucheon 14662, Republic of Korea
| | - Hyotcherl Ihee
- Department of Chemistry and KI for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.,Center for Nanomaterials and Chemical Reactions, Institute for Basic Science (IBS), Daejeon 34141, Republic of Korea
| | - Jeongho Kim
- Department of Chemistry, Inha University, 100 Inha-ro, Michuhol-gu, Incheon 22212, Republic of Korea
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3
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Shirota H. Intermolecular Vibrations and Diffusive Orientational Dynamics of Cs Condensed Ring Aromatic Molecular Liquids. J Phys Chem A 2011; 115:14262-75. [DOI: 10.1021/jp208389n] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Hideaki Shirota
- Department of Nanomaterial Science, Graduate School of Advanced Integration Science & Department of Chemistry, Faculty of Science, Chiba University, 1-33 Yayoi, Inage-ku, Chiba 263-8522, Japan
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4
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Yamaguchi S, Mazur K, Heisler IA, Shirota H, Tominaga K, Meech SR. Low-frequency modes of the benzoic acid dimer in chloroform observed by the optical Kerr effect. J Chem Phys 2011; 135:134504. [DOI: 10.1063/1.3635778] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
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5
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Yamaguchi S, Tominaga K, Saito S. Intermolecular vibrational mode of the benzoic acid dimer in solution observed by terahertz time-domain spectroscopy. Phys Chem Chem Phys 2011; 13:14742-9. [DOI: 10.1039/c1cp20912d] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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6
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Smith NA, Meech SR. Optically-heterodyne-detected optical Kerr effect (OHD-OKE): Applications in condensed phase dynamics. INT REV PHYS CHEM 2010. [DOI: 10.1080/01442350110092701] [Citation(s) in RCA: 165] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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7
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Fujisawa T, Nishikawa K, Shirota H. Comparison of interionic/intermolecular vibrational dynamics between ionic liquids and concentrated electrolyte solutions. J Chem Phys 2009; 131:244519. [DOI: 10.1063/1.3280028] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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8
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Shirota H, Fujisawa T, Fukazawa H, Nishikawa K. Ultrafast Dynamics in Aprotic Molecular Liquids: A Femtosecond Raman-Induced Kerr Effect Spectroscopic Study. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2009. [DOI: 10.1246/bcsj.82.1347] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Heisler IA, Meech SR. Polarization-Resolved Ultrafast Polarizability Relaxation in Polar Aromatic Liquids. J Phys Chem B 2008; 112:12976-84. [DOI: 10.1021/jp805862z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Ismael A. Heisler
- School of Chemical Sciences, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Stephen R. Meech
- School of Chemical Sciences, University of East Anglia, Norwich NR4 7TJ, United Kingdom
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10
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Hunt NT, Jaye AA, Meech SR. Ultrafast dynamics in complex fluids observed through the ultrafast optically-heterodyne-detected optical-Kerr-effect (OHD-OKE). Phys Chem Chem Phys 2007; 9:2167-80. [PMID: 17487314 DOI: 10.1039/b616078f] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The ultrafast molecular dynamics of complex fluids have been recorded using the optically-heterodyne-detected optical-Kerr-effect (OHD-OKE). The OHD-OKE method is reviewed and some recent refinements to the method are described. Applications to a range of complex fluids, including microemulsions, polymer melts and solutions, liquid crystal and ionic liquids are surveyed. The level of detail attainable with the OHD-OKE method in these complex fluids is discussed. The prospects for future experiments are discussed.
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Affiliation(s)
- Neil T Hunt
- School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich, UK NR4 7TJ
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11
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Elola MD, Ladanyi BM. Molecular Dynamics Study of Polarizability Anisotropy Relaxation in Aromatic Liquids and Its Connection with Local Structure. J Phys Chem B 2006; 110:15525-41. [PMID: 16884276 DOI: 10.1021/jp062071b] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The collective polarizability anisotropy dynamics in a set of three aromatic liquids, benzene (Bz), hexafluorobenzene (HFB), and 1,3,5-trifluorobenzene (TFB), has been studied by molecular dynamics simulation. These liquids have very similar shapes, but different electrostatic interactions due to opposite polarities of C-H and C-F bonds, giving rise to different local intermolecular structures in the liquid phase. We have investigated how these structural arrangements affect polarizability anisotropy dynamics observed in optical Kerr-effect (OKE) spectroscopy. We have modeled the interaction-induced polarizability with the first-order dipole-induced dipole approximation, with the molecular polarizability distributed over the carbon sites. Local contributions to the librational OKE spectrum were computed separately for molecules participating in parallel or perpendicular relative orientations within the first coordination shell. We found that the relative locations of parallel and perpendicular librational bands of the OKE spectra are closely related to the corresponding pair energy distributions of the closest four neighbors of a given molecule, corresponding to a model of a harmonic oscillator in a cage of nearest neighbors. This model predicts higher librational frequencies for more attractive intermolecular interactions, which in all three liquids correspond to parallel local arrangements. On the diffusive orientational time scale, all three liquids exhibit slower relaxation of molecules in parallel arrangements, although the difference in relaxation rates is substantial only in TFB, which has the strongest tendency toward parallel stacking. The analysis of the collective polarizability relaxation was performed using two different approaches, the projection scheme (J. Chem. Phys. 1980, 72, 2801) and the theory developed by Steele (Mol. Phys. 1987, 61, 1031) for the second time derivatives applied to collective time correlations. Both approaches allow the decomposition of the OKE response into contributions from orientational relaxation and other dynamical processes. We find that they lead to different predictions on how the response depends on collective reorientation and processes arising from fluctuations in the interaction-induced polarizability. We discuss the reasons for these differences and the advantages and disadvantages of the two analysis schemes.
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Affiliation(s)
- M Dolores Elola
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, USA.
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12
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Loughnane BJ, Scodinu A, Fourkas JT. Temperature-Dependent Optical Kerr Effect Spectroscopy of Aromatic Liquids. J Phys Chem B 2006; 110:5708-20. [PMID: 16539516 DOI: 10.1021/jp055627o] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Ultrafast optical Kerr effect (OKE) spectroscopy has been used to study the temperature-dependent dynamics of five aromatic liquids: benzene, benzene-d(6), hexafluorobenzene, mesitylene, and 1,3,5-trifluorobenzene. The intermediate response time of all of the liquids was found to scale with the collective orientational correlation time, as has been observed for other simple liquids. The spectra of hexafluorobenzene, 1,3,5-trifluorobenzene, and mesitylene are qualitatively different from those of the other liquids and exhibit different behavior with temperature. These spectra allow us to assess the influence of different molecular parameters on the shape of the OKE spectrum. On the basis of these data, we propose a model that links the differences in the OKE spectra to corresponding differences in the local ordering of the liquids.
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Affiliation(s)
- Brian J Loughnane
- Eugene F. Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, USA
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13
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Jaye AA, Hunt NT, Meech SR. Temperature- and solvation-dependent dynamics of liquid sulfur dioxide studied through the ultrafast optical Kerr effect. J Chem Phys 2006; 124:024506. [PMID: 16422610 DOI: 10.1063/1.2145760] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The ultrafast dynamics of liquid sulphur dioxide have been studied over a wide temperature range and in solution. The optically heterodyne-detected and spatially masked optical Kerr effect (OKE) has been used to record the anisotropic and isotropic third-order responses, respectively. Analysis of the anisotropic response reveals two components, an ultrafast nonexponential relaxation and a slower exponential relaxation. The slower component is well described by the Stokes-Einstein-Debye equation for diffusive orientational relaxation. The simple form of the temperature dependence and the agreement between collective (OKE) and single molecule (e.g., NMR) measurements of the orientational relaxation time suggests that orientational pair correlation is not significant in this liquid. The relative contributions of intermolecular interaction-induced and single-molecule orientational dynamics to the ultrafast part of the spectral density are discussed. Single-molecule librational-orientational dynamics appear to dominate the ultrafast OKE response of liquid SO2. The temperature-dependent OKE data are transformed to the frequency domain to yield the Raman spectral density for the low-frequency intermolecular modes. These are bimodal with the lowest-frequency component arising from diffusive orientational relaxation and a higher-frequency component connected with the ultrafast time-domain response. This component is characterized by a shift to higher frequency at lower temperature. This result is analyzed in terms of a harmonic librational oscillator model, which describes the data accurately. The observed spectral shifts with temperature are ascribed to increasing intermolecular interactions with increasing liquid density. Overall, the dynamics of liquid SO2 are found to be well described in terms of molecular orientational relaxation which is controlled over every relevant time range by intermolecular interactions.
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Affiliation(s)
- Andrew A Jaye
- School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich NR4 7TJ, United Kingdom
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Tao G, Stratt RM. Why Does the Intermolecular Dynamics of Liquid Biphenyl so Closely Resemble that of Liquid Benzene? Molecular Dynamics Simulation of the Optical-Kerr-Effect Spectra. J Phys Chem B 2005; 110:976-87. [PMID: 16471632 DOI: 10.1021/jp0558932] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The combination of optical-Kerr-effect (OKE) spectroscopy and molecular dynamics simulations has provided us with a newfound ability to delve into the librational dynamics of liquids, revealing, in the process, some surprising commonalities among aromatic liquids. Benzene and biphenyl, for example, have remarkably similar OKE spectra despite marked differences in their shapes, sizes, and moments of inertia--and even more chemically distinct aromatics tend to have noticeable similarities in their spectra. We explore this universality by using a molecular dynamics simulation to investigate the librational dynamics of molten biphenyl and to predict its OKE spectrum, comparing the results with our previous calculations for liquid benzene. We suggest that the impressive level of quantitative agreement between these two liquids is largely a reflection of the fact that librations in these and other aromatic liquids act as torsional oscillations with oscillator frequencies selected from the liquid's librational bands. Since these bands are centered about the librational Einstein frequencies, the quantitative similarities between the liquids are essentially reflections of the near identities of their Einstein frequencies. Why then are the Einstein frequencies themselves so insensitive to molecular details? We show that, for nearly planar molecules, mean-square torques and moments of inertia tend to scale with molecular dimensions in much the same way. We demonstrate that this near cancellation provides both a quantitative explanation of the close relationship between benzene and biphenyl and a more general perspective on the similarities seen in the ultrafast dynamics of aromatic liquids.
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Affiliation(s)
- Guohua Tao
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
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15
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Elola MD, Ladanyi BM, Scodinu A, Loughnane BJ, Fourkas JT. Effects of Molecular Association on Polarizability Relaxation in Liquid Mixtures of Benzene and Hexafluorobenzene. J Phys Chem B 2005; 109:24085-99. [PMID: 16375401 DOI: 10.1021/jp054733n] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this work we have studied the relaxation dynamics of the many-body polarizability anisotropy in liquid mixtures of benzene (Bz) and hexafluorobenzene (Hf) at room temperature by femtosecond optical heterodyne-detected Raman-induced Kerr effect spectroscopy (OHD-RIKES) experiments and molecular dynamics (MD) simulations. The computed polarizability response arising from intermolecular interactions was included using the first-order dipole-induced-dipole model with the molecular polarizability distributed over the carbon sites of each molecule. We found good qualitative agreement between experiments and simulations in the features exhibited by the nuclear response function R(t) for pure liquids and mixtures. The long-time diffusive decay of R(t) was observed to vary substantially with composition, slowing down noticeably with dilution of each of the species as compared with that in the corresponding pure liquids. MD simulation shows that the effect on R(t) is due to the formation of strong and localized intermolecular association between Bz and Hf species that hinder the rotational diffusive dynamics. The formation of these Bz-Hf complexes in the liquid mixtures also modifies the rotational diffusive dynamics of the component species in such a way that cannot be explained solely in terms of a viscosity effect. Even though the computed orientational diffusive relaxation times associated with Bz and Hf are larger by a factor of approximately 2 than those from experiments, we found similar trends in experiments and simulations for these characteristic times as a function of composition. Namely, the collective and single-molecule orientational correlation times associated with Bz are observed to grow monotonically with the dilution of Bz, while those corresponding to Hf species exhibit a maximum at the equimolar composition. We attribute the quantitative discrepancy between experiments and simulations to the use of the Williams potential, which seems to overestimate the intermolecular interactions and thus predicts not only a slower translational dynamics but also a slower rotational diffusion dynamics than in real fluids.
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Affiliation(s)
- M Dolores Elola
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, USA.
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Shirota H, Castner EW. Why Are Viscosities Lower for Ionic Liquids with −CH2Si(CH3)3 vs −CH2C(CH3)3 Substitutions on the Imidazolium Cations? J Phys Chem B 2005; 109:21576-85. [PMID: 16853801 DOI: 10.1021/jp053930j] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
We have prepared novel room temperature ionic liquids (RTILs) with trimethylsilylmethyl (TMSiM)-substituted imidazolium cations and compared the properties of these liquids with those for which the TMSiM group is replaced by the analogous neopentyl group. The ionic liquids are prepared with both tetrafluoroborate (BF(4)(-)) and bis(trifluoromethylsulfonyl)imide (NTf(2)(-)) anions paired with the imidazolium cations. At 22 degrees C, the TMSiM-substituted imidazolium ILs have shear viscosities that are reduced by a factor of 1.6 and 7.4 relative to the alkylimidazolium ILs for the NTf(2)(-) and BF(4)(-) anions, respectively. To understand the effect of silicon substitution on the viscosity, the charge densities have been calculated by using density functional theory electronic structure calculations. The ultrafast intermolecular, vibrational, and orientational dynamics of these RTILs have been measured by using femtosecond optical heterodyne-detected Raman-induced Kerr effect spectroscopy (OHD-RIKES). The intermolecular dynamical spectrum provides an estimate of the strength of interactions between the ions in the RTILs, and provides a qualitative explanation for the observed reduction in viscosity for the silicon-substituted RTILs.
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Affiliation(s)
- Hideaki Shirota
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, New Jersey 08854-8087, USA.
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Shirota H, Funston AM, Wishart JF, Castner EW. Ultrafast dynamics of pyrrolidinium cation ionic liquids. J Chem Phys 2005; 122:184512. [PMID: 15918734 DOI: 10.1063/1.1893797] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
We have investigated the ultrafast molecular dynamics of five pyrrolidinium cation room temperature ionic liquids using femtosecond optical heterodyne-detected Raman-induced Kerr effect spectroscopy. The ionic liquids studied are N-butyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide P14+/NTf2-), N-methoxyethyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide P1EOE+/NTf2-), N-ethoxyethyl-N-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide P1EOE+/NTf2-), N-ethoxyethyl-N-methylpyrrolidinium bromide P1EOE+, and N-ethoxyethyl-N-methylpyrrolidinium dicyanoamide P1EOE+/DCA-). For comparing dynamics among the five ionic liquids, we categorize the ionic liquids into two groups. One group of liquids comprises the three pyrrolidinium cations P14+, P1EOM+, and P1EOE+ paired with the NTf2- anion. The other group of liquids consists of the P1EOE+ cation paired with each of the three anions NTf2-, Br-, and DCA-. The overdamped relaxation for time scales longer than 2 ps has been fit by a triexponential function for each of the five pyrrolidinium ionic liquids. The fast ( approximately 2 ps) and intermediate (approximately 20 ps) relaxation time constants vary little among these five ionic liquids. However, the slow relaxation time constant correlates with the viscosity. Thus, the Kerr spectra in the range from 0 to 750 cm(-1) are quite similar for the group of three pyrrolidinium ionic liquids paired with the NTf2- anion. The intermolecular vibrational line shapes between 0 and 150 cm(-1) are fit to a multimode Brownian oscillator model; adequate fits required at least three modes to be included in the line shape.
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Affiliation(s)
- Hideaki Shirota
- Department of Chemistry & Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854-8087, USA
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Shirota H. Ultrafast Dynamics of Liquid Poly(ethylene glycol)s and Crown Ethers Studied by Femtosecond Raman-Induced Kerr Effect Spectroscopy. J Phys Chem B 2005; 109:7053-62. [PMID: 16851802 DOI: 10.1021/jp044125s] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Ultrafast molecular dynamics of liquid poly(ethylene glycol)s, tetra(ethylene glycol), penta(ethylene glycol), and poly(ethylene glycol) with the molecular weight of 600, and crown ethers, 12-crown-4 and 15-crown-5, have been investigated by means of femtosecond optical heterodyne-detected Raman-induced Kerr effect spectroscopy. Picosecond Kerr transients of poly(ethylene glycol)s and crown ethers are characterized by a biexponential function with the time constants of about 2 and 20 ps. Both the faster and slower time constants do not vary much among the five oligo(ethylene oxide)s. Femtosecond dynamics is discussed based on the Kerr (depolarized Raman) spectra obtained by Fourier transform deconvolution analysis of the high time resolution Kerr transients. The broad low-frequency band (0-200 cm(-1)) in the Kerr spectrum is analyzed by two Brownian oscillators. The spectral shapes of linear poly(ethylene glycol) and cyclic crown ether are very different. Both the low- and high-frequency Brownian oscillators for crown ethers show lower frequency and broader spectral features than those for poly(ethylene glycol)s. The comparison of the low-frequency spectra of poly(ethylene glycol)s and crown ethers shows that the low-frequency spectrum of 15-crown-5 is closer to that of poly(ethylene glycol)s than that of 12-crown-4 is. The difference of the low-frequency spectra between poly(ethylene glycol) and crown ether is discussed with the concepts of molecular conformation and liquid density. The features of the observed intramolecular vibrational bands are also correlated with the molecular conformations.
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Affiliation(s)
- Hideaki Shirota
- Department of General Systems Sciences, Graduate School of Arts & Sciences, University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
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Jaye AA, Hunt NT, Meech SR. Ultrafast dynamics in the dispersed phase of oil-in-water microemulsions: monosubstituted benzenes incorporated into dodecyltrimethylammonium bromide (DTAB) aqueous micelles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:1238-1243. [PMID: 15697266 DOI: 10.1021/la047599r] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Time-resolved optical Kerr effect spectroscopy has been used to probe the molecular environment afforded by the hydrophobic core of oil-in-water microemulsions. This was achieved by measuring the ultrafast dynamics of a series of benzene derivatives (benzonitrile, nitrobenzene, fluorobenzene, styrene, and toluene) incorporated as the oil phase within oil-in-water microemulsions and comparing them to the dynamics in neat liquid and the liquid diluted in nonpolar solvent. Polar and strongly interacting liquids (benzonitrile and nitrobenzene) showed dynamics in the microemulsion that are similar to those in the solution phase, while weakly interacting and mildly polar liquids (fluorobenzene, styrene and toluene) reveal dynamics more similar to those of the neat liquid. This suggests stabilization of the polar dispersed phase in polar regions of the micelle.
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Affiliation(s)
- Andrew A Jaye
- School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich NR4 7TJ, UK
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Shirota H. Ultrafast molecular dynamics of liquid aromatic molecules and the mixtures with CCl4. J Chem Phys 2005; 122:44514. [PMID: 15740274 DOI: 10.1063/1.1840420] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The ultrafast molecular dynamics of liquid aromatic molecules, benzene, toluene, ethylbenzene, cumene, and 1,3-diphenylpropane, and the mixtures with CCl(4) have been investigated by means of femtosecond optical heterodyne-detected Raman-induced Kerr effect spectroscopy. The picosecond Kerr transients of benzene, toluene, ethylbenzene, and cumene and the mixtures with CCl(4) show a biexponential feature. 1,3-Diphenylpropane and the mixtures with CCl(4) show triexponential picosecond Kerr transients. The slow relaxation time constants of the aromatic molecules and the mixtures with CCl(4) are qualitatively described by the Stoke-Einstein-Debye hydrodynamic model. The ultrafast dynamics have been discussed based on the Kerr spectra in the frequency range of 0-800 cm(-1) obtained by the Fourier transform analysis of the Kerr transients. The line shapes of the low-frequency intermolecular spectra located at 0-180 cm(-1) frequency range have been analyzed by two Brownian oscillators ( approximately 11 cm(-1) and approximately 45 cm(-1) peaks) and an antisymmetric Gaussian function ( approximately 65 cm(-1) peak). The spectrum shape of 1,3-diphenylpropane is quite different from the spectrum shapes of the other aromatic molecules for the low magnitude of the low-frequency mode of 1,3-diphenylpropane and/or an intramolecular vibration. Although the concentration dependences of the low- and intermediate-frequency intermolecular modes (Brownian oscillators) do not show a significant trend, the width of high-frequency intermolecular mode (antisymmetric Gaussian) becomes narrower with the higher CCl(4) concentration for all the aromatics mixtures with CCl(4). The result indicates that the inhomogeneity of the intermolecular vibrational mode in aromatics/CCl(4) mixtures is decreasing with the lower concentration of aromatics. The intramolecular vibrational modes of the aromatic molecules observed in the Kerr spectra are also shown with the calculation results based on the density functional theory.
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Affiliation(s)
- Hideaki Shirota
- Department of General Systems Sciences, Graduate School of Arts and Sciences, University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
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Rajian JR, Hyun BR, Quitevis EL. Intermolecular Spectrum of Liquid Biphenyl Studied by Optical Kerr Effect Spectroscopy. J Phys Chem A 2004. [DOI: 10.1021/jp047415h] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Justin Rajesh Rajian
- Department of Chemistry and Biochemistry and Department of Physics, Texas Tech University, Lubbock, Texas 79409
| | - Byung-Ryool Hyun
- Department of Chemistry and Biochemistry and Department of Physics, Texas Tech University, Lubbock, Texas 79409
| | - Edward L. Quitevis
- Department of Chemistry and Biochemistry and Department of Physics, Texas Tech University, Lubbock, Texas 79409
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Morandeira A, Fürstenberg A, Vauthey E. Fluorescence Quenching in Electron-Donating Solvents. 2. Solvent Dependence and Product Dynamics. J Phys Chem A 2004. [DOI: 10.1021/jp048048c] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Ana Morandeira
- Department of Physical Chemistry of the University of Geneva, 30 quai Ernest-Ansermet, CH-1211 Genève 4, Switzerland
| | - Alexandre Fürstenberg
- Department of Physical Chemistry of the University of Geneva, 30 quai Ernest-Ansermet, CH-1211 Genève 4, Switzerland
| | - Eric Vauthey
- Department of Physical Chemistry of the University of Geneva, 30 quai Ernest-Ansermet, CH-1211 Genève 4, Switzerland
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23
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Ryu S, Stratt RM. A Case Study in the Molecular Interpretation of Optical Kerr Effect Spectra: Instantaneous-Normal-Mode Analysis of the OKE Spectrum of Liquid Benzene. J Phys Chem B 2004. [DOI: 10.1021/jp0375665] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Seol Ryu
- Department of Chemistry, Brown University, Providence, Rhode Island 02912
| | - Richard M. Stratt
- Department of Chemistry, Brown University, Providence, Rhode Island 02912
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Hunt NT, Jaye AA, Hellman A, Meech SR. Ultrafast Dynamics of Styrene Microemulsions, Polystyrene Nanolatexes, and Structural Analogues of Polystyrene. J Phys Chem B 2003. [DOI: 10.1021/jp035624g] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Neil T. Hunt
- School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Andrew A. Jaye
- School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Alexander Hellman
- School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Stephen R. Meech
- School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich NR4 7TJ, United Kingdom
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25
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Palit DK, Zhang T, Kumazaki S, Yoshihara K. Hydrogen-Bond Dynamics in the Excited State of Coumarin 102−Aniline Hydrogen-Bonded Complex. J Phys Chem A 2003. [DOI: 10.1021/jp030633a] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Dipak K. Palit
- Radiation Chemistry & Chemical Dynamics Division, Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400 085, India, and School of Materials Science, Japan Advanced Institute of Science and Technology, Tatsunokuchi, Ishikawa 923-1292, Japan
| | - Tieqiao Zhang
- Radiation Chemistry & Chemical Dynamics Division, Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400 085, India, and School of Materials Science, Japan Advanced Institute of Science and Technology, Tatsunokuchi, Ishikawa 923-1292, Japan
| | - Shigeichi Kumazaki
- Radiation Chemistry & Chemical Dynamics Division, Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400 085, India, and School of Materials Science, Japan Advanced Institute of Science and Technology, Tatsunokuchi, Ishikawa 923-1292, Japan
| | - Keitaro Yoshihara
- Radiation Chemistry & Chemical Dynamics Division, Chemistry Group, Bhabha Atomic Research Centre, Mumbai 400 085, India, and School of Materials Science, Japan Advanced Institute of Science and Technology, Tatsunokuchi, Ishikawa 923-1292, Japan
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26
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Hunt NT, Jaye AA, Meech SR. Ultrafast Dynamics in Microemulsions: Optical Kerr Effect Study of the Dispersed Oil Phase in a Carbon Disulfide−Dodecyltrimethylammonium Bromide−Water Microemulsion. J Phys Chem B 2003. [DOI: 10.1021/jp022301w] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Neil T. Hunt
- School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich NR4 7TJ, U.K
| | - Andrew A. Jaye
- School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich NR4 7TJ, U.K
| | - Stephen R. Meech
- School of Chemical Sciences and Pharmacy, University of East Anglia, Norwich NR4 7TJ, U.K
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27
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Luther BM, Kimmel JR, Levinger NE. Dynamics of polar solvation in acetonitrile–benzene binary mixtures: Role of dipolar and quadrupolar contributions to solvation. J Chem Phys 2002. [DOI: 10.1063/1.1436074] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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28
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Shirota H, Castner EW. Ultrafast dynamics in aqueous polyacrylamide solutions. J Am Chem Soc 2001; 123:12877-85. [PMID: 11749546 DOI: 10.1021/ja010290z] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have investigated the ultrafast dynamics of aqueous polyacrylamide ([-CH(2)CH(CONH(2))-](n), or PAAm) solutions using femtosecond optical heterodyne-detected Raman-induced Kerr effect spectroscopy (OHD-RIKES). The observed aqueous PAAm dynamics are nearly identical for both M(w) = 1500 and 10 000. Aqueous propionamide (CH(3)CH(2)CONH(2), or PrAm) solutions were also studied, because PrAm is an exact model for the PAAm constitutional repeat unit (CRU). The longest time scale dynamics observed for both aqueous PAAm and PrAm solutions occur in the 4-10 ps range. Over the range of concentrations from 0 to 40 wt %, the picosecond reorientation time constants for the aqueous PAAm and PrAm solutions scale linearly with the solution concentration, despite the fact that the solution shear viscosities vary exponentially from 1 to 264 cP. For a given value of solution concentration in weight percent, constant ratios of measured reorientation time constants for PAAm to PrAm are obtained. This ratio of PAAm to PrAm reorientation time constants is equal to the ratio of the volume for the PAAm constitutional repeat unit (-CH(2)CHCONH(2)-) to the molecular volume of PrAm. For these reasons, we assign the polymer reorientation dynamics to motions of the entire constitutional repeat unit, not only side group motions. Simple molecular dynamics simulations of H[-CH(2)CH(CONH(2))-](7)H in a periodic box with 180 water molecules support this assignment. Amide-amide and amide-water hydrogen-bonding interactions lead to strongly oscillatory femtosecond dynamics in the Kerr transients, peaking at 80, 410, and 750 fs.
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Affiliation(s)
- H Shirota
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, 610 Taylor Road, Piscataway, NJ 08854-8087, USA.
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Smith NA, Meech SR. Ultrafast Dynamics of Polar Monosubstituted Benzene Liquids Studied by the Femtosecond Optical Kerr Effect. J Phys Chem A 2000. [DOI: 10.1021/jp993170a] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Neil A. Smith
- School of Chemical Sciences, University of East Anglia, Norwich NR4 7TJ, U.K
| | - Stephen R. Meech
- School of Chemical Sciences, University of East Anglia, Norwich NR4 7TJ, U.K
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Loughnane BJ, Scodinu A, Farrer RA, Fourkas JT, Mohanty U. Exponential intermolecular dynamics in optical Kerr effect spectroscopy of small-molecule liquids. J Chem Phys 1999. [DOI: 10.1063/1.479544] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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31
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Bartolini P, Ricci M, Torre R, Righini R, Sánta I. Diffusive and oscillatory dynamics of liquid iodobenzene measured by femtosecond optical Kerr effect. J Chem Phys 1999. [DOI: 10.1063/1.478773] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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32
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Solvent dynamics derived from optical Kerr effect, dielectric dispersion, and time-resolved stokes shift measurements: an empirical comparison. J Mol Liq 1998. [DOI: 10.1016/s0167-7322(98)00066-x] [Citation(s) in RCA: 146] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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33
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Shirota H, Pal H, Tominaga K, Yoshihara K. Substituent Effect and Deuterium Isotope Effect of Ultrafast Intermolecular Electron Transfer: Coumarin in Electron-Donating Solvent. J Phys Chem A 1998. [DOI: 10.1021/jp973376g] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hideaki Shirota
- The Graduate University for Advanced Studies, Myodaiji, Okazaki 444, Japan, and Institute for Molecular Science, Myodaiji, Okazaki 444, Japan
| | - Haridas Pal
- The Graduate University for Advanced Studies, Myodaiji, Okazaki 444, Japan, and Institute for Molecular Science, Myodaiji, Okazaki 444, Japan
| | - Keisuke Tominaga
- The Graduate University for Advanced Studies, Myodaiji, Okazaki 444, Japan, and Institute for Molecular Science, Myodaiji, Okazaki 444, Japan
| | - Keitaro Yoshihara
- The Graduate University for Advanced Studies, Myodaiji, Okazaki 444, Japan, and Institute for Molecular Science, Myodaiji, Okazaki 444, Japan
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Smith NA, Lin S, Meech SR, Shirota H, Yoshihara K. Ultrafast Dynamics of Liquid Anilines Studied by the Optical Kerr Effect. J Phys Chem A 1997. [DOI: 10.1021/jp9722925] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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