1
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Khudozhitkov AE, Stange P, Paschek D, Stepanov AG, Kolokolov DI, Ludwig R. The Influence of Deuterium Isotope Effects on Structural Rearrangements, Ensemble Equilibria, and Hydrogen Bonding in Protic Ionic Liquids. Chemphyschem 2022; 23:e202200557. [PMID: 35944124 PMCID: PMC10087857 DOI: 10.1002/cphc.202200557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Indexed: 01/05/2023]
Abstract
We report strong isotope effects for the protic ionic liquid triethylammonium methanesulfonate [TEA][OMs] by means of deuterium solid-state NMR spectroscopy covering broad temperature ranges from 65 K to 313 K. Both isotopically labelled PILs differ in non-deuterated and fully deuterated ethyl groups of the triethyl ammonium cations. The N-D bond of both cations is used as sensitive probe for hydrogen bonding and structural ordering. The 2 H NMR line shape analysis provides the deuteron quadrupole coupling constants and the characteristics of a broad heterogeneous phase with simultaneously present static and mobile states indicating plastic crystal behavior. The temperatures where both states are equally populated differ by about 80 K for the two PILs, showing that deuteration of the ethyl groups in the trialkylammonium cations tremendously shifts the equilibrium towards the static state. In addition, it leads to a significant less cooperative transition, associated with a significantly reduced standard molar transition entropy.
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Affiliation(s)
- Alexander E Khudozhitkov
- Boreskov Institute of Catalysis, Siberian Branch of Russian Academy of Sciences, Prospekt Akademika Lavrentieva 5, Novosibirsk, 630090, Russia.,Novosibirsk State University, Pirogova Street 2, Novosibirsk, 630090, Russia
| | - Peter Stange
- Universität Rostock, Institut für Chemie, Abteilung für Physikalische Chemie, Albert-Einstein-Straße 27, 18059, Rostock, Germany
| | - Dietmar Paschek
- Universität Rostock, Institut für Chemie, Abteilung für Physikalische Chemie, Albert-Einstein-Straße 27, 18059, Rostock, Germany
| | - Alexander G Stepanov
- Boreskov Institute of Catalysis, Siberian Branch of Russian Academy of Sciences, Prospekt Akademika Lavrentieva 5, Novosibirsk, 630090, Russia
| | - Daniil I Kolokolov
- Boreskov Institute of Catalysis, Siberian Branch of Russian Academy of Sciences, Prospekt Akademika Lavrentieva 5, Novosibirsk, 630090, Russia.,Novosibirsk State University, Pirogova Street 2, Novosibirsk, 630090, Russia
| | - Ralf Ludwig
- Universität Rostock, Institut für Chemie, Abteilung für Physikalische Chemie, Albert-Einstein-Straße 27, 18059, Rostock, Germany.,Leibniz-Institut für Katalyse an der Universität Rostock e.V., Albert-Einstein-Str. 29a, 18059, Rostock, Germany
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2
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Becher M, Lichtinger A, Minikejew R, Vogel M, Rössler EA. NMR Relaxometry Accessing the Relaxation Spectrum in Molecular Glass Formers. Int J Mol Sci 2022; 23:ijms23095118. [PMID: 35563506 PMCID: PMC9105706 DOI: 10.3390/ijms23095118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/29/2022] [Accepted: 04/29/2022] [Indexed: 12/10/2022] Open
Abstract
It is a longstanding question whether universality or specificity characterize the molecular dynamics underlying the glass transition of liquids. In particular, there is an ongoing debate to what degree the shape of dynamical susceptibilities is common to various molecular glass formers. Traditionally, results from dielectric spectroscopy and light scattering have dominated the discussion. Here, we show that nuclear magnetic resonance (NMR), primarily field-cycling relaxometry, has evolved into a valuable method, which provides access to both translational and rotational motions, depending on the probe nucleus. A comparison of 1H NMR results indicates that translation is more retarded with respect to rotation for liquids with fully established hydrogen-bond networks; however, the effect is not related to the slow Debye process of, for example, monohydroxy alcohols. As for the reorientation dynamics, the NMR susceptibilities of the structural (α) relaxation usually resemble those of light scattering, while the dielectric spectra of especially polar liquids have a different broadening, likely due to contributions from cross correlations between different molecules. Moreover, NMR relaxometry confirms that the excess wing on the high-frequency flank of the α-process is a generic relaxation feature of liquids approaching the glass transition. However, the relevance of this feature generally differs between various methods, possibly because of their different sensitivities to small-amplitude motions. As a major advantage, NMR is isotope specific; hence, it enables selective studies on a particular molecular entity or a particular component of a liquid mixture. Exploiting these possibilities, we show that the characteristic Cole-Davidson shape of the α-relaxation is retained in various ionic liquids and salt solutions, but the width parameter may differ for the components. In contrast, the low-frequency flank of the α-relaxation can be notably broadened for liquids in nanoscopic confinements. This effect also occurs in liquid mixtures with a prominent dynamical disparity in their components.
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Affiliation(s)
- Manuel Becher
- Nordbayerisches NMR Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany; (M.B.); (A.L.); (R.M.)
| | - Anne Lichtinger
- Nordbayerisches NMR Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany; (M.B.); (A.L.); (R.M.)
| | - Rafael Minikejew
- Nordbayerisches NMR Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany; (M.B.); (A.L.); (R.M.)
| | - Michael Vogel
- Institut für Physik Kondensierter Materie, Technische Universität Darmstadt, 64289 Darmstadt, Germany;
| | - Ernst A. Rössler
- Nordbayerisches NMR Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany; (M.B.); (A.L.); (R.M.)
- Correspondence:
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3
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Becher M, Flämig M, Rössler EA. Field-cycling 31P and 1H NMR relaxometry studying the reorientational dynamics of glass forming organophosphates. J Chem Phys 2022; 156:074502. [DOI: 10.1063/5.0082566] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- M. Becher
- Nordbayerisches NMR-Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
| | - M. Flämig
- Nordbayerisches NMR-Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
| | - E. A. Rössler
- Nordbayerisches NMR-Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
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4
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Becher M, Körber T, Döß A, Hinze G, Gainaru C, Böhmer R, Vogel M, Rössler EA. Nuclear Spin Relaxation in Viscous Liquids: Relaxation Stretching of Single-Particle Probes. J Phys Chem B 2021; 125:13519-13532. [PMID: 34860530 DOI: 10.1021/acs.jpcb.1c06722] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Spin-lattice relaxation rates R1(ω,T), probed via high-field and field-cycling nuclear magnetic resonance (NMR), are used to test the validity of frequency-temperature superposition (FTS) for the reorientation dynamics in viscous liquids. For several liquids, FTS is found to apply so that master curves can be generated. The susceptibility spectra are highly similar to those obtained from depolarized light scattering (DLS) and reveal an excess wing. Where FTS works, two approaches are suggested to access the susceptibility: (i) a plot of deuteron R1(T) vs the spin-spin relaxation rate R2(T) and (ii) a plot of R1(T) vs an independently measured reference time τref(T). Using single-frequency scans, (i) allows one to extract the relaxation stretching as well as the NMR coupling constant. Surveying 26 data sets, we find Kohlrausch functions with exponents 0.39 < βK ≤ 0.67. Plots of the spin-spin relaxation rate R2─rescaled by the NMR coupling constant─as a function of temperature allow one to test how well site-specific NMR relaxations couple to a given reference process. Upon cooling of flexible molecule liquids, the site-specific dynamics is found to merge, suggesting that near Tg the molecules reorient essentially as a rigid entity. This presents a possible resolution for the much lower stretching parameters reported here at high temperatures that contrast with the ones that were reported to be universal in a recent DLS study close to Tg. Our analysis underlines that deuteron relaxation is a uniquely powerful tool to probe single-particle reorientation.
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Affiliation(s)
- M Becher
- Anorganische Chemie III and Nordbayerisches NMR Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Th Körber
- Anorganische Chemie III and Nordbayerisches NMR Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
| | - A Döß
- Department Chemie, Johannes Gutenberg-Universität, 55128 Mainz, Germany
| | - G Hinze
- Department Chemie, Johannes Gutenberg-Universität, 55128 Mainz, Germany
| | - C Gainaru
- Fakultät Physik, Technische Universität Dortmund, 44221 Dortmund, Germany.,Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - R Böhmer
- Fakultät Physik, Technische Universität Dortmund, 44221 Dortmund, Germany
| | - M Vogel
- Institut für Physik kondensierter Materie, Technische Universität Darmstadt, 64289 Darmstadt, Germany
| | - E A Rössler
- Anorganische Chemie III and Nordbayerisches NMR Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
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5
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Abstract
Abstract
Beta-detected NMR is a type of nuclear magnetic resonance that uses the asymmetric property of radioactive beta decay to provide a “nuclear” detection scheme. It is vastly more sensitive than conventional NMR on a per nuclear spin basis but requires a suitable radioisotope. I briefly present the general aspects of the method and its implementation at TRIUMF, where ion implantation of the NMR radioisotope is used to study a variety of samples including crystalline solids and thin films, and more recently, soft matter and even room temperature ionic liquids. Finally, I review the progress of the TRIUMF βNMR program in the period 2015–2021.
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Affiliation(s)
- W. Andrew MacFarlane
- Department of Chemistry , University of British Columbia , Vancouver , BC , 2036, Main Mall, V6T 1Z1 , Canada
- Stewart Blusson Quantum Matter Institute, University of British Columbia, , Vancouver , BC , 2355, East Mall, V6T 1Z4 , Canada
- TRUMF, , Vancouver , BC , 4004 , Wesbrook Mall , V6T 2A3 , Canada
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6
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Hodge SR, Berg MA. Nonlinear measurements of kinetics and generalized dynamical modes. I. Extracting the one-dimensional Green's function from a time series. J Chem Phys 2021; 155:024122. [PMID: 34266246 DOI: 10.1063/5.0053422] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Often, a single correlation function is used to measure the kinetics of a complex system. In contrast, a large set of k-vector modes and their correlation functions are commonly defined for motion in free space. This set can be transformed to the van Hove correlation function, which is the Green's function for molecular diffusion. Here, these ideas are generalized to other observables. A set of correlation functions of nonlinear functions of an observable is used to extract the corresponding Green's function. Although this paper focuses on nonlinear correlation functions of an equilibrium time series, the results are directly connected to other types of nonlinear kinetics, including perturbation-response experiments with strong fields. Generalized modes are defined as the orthogonal polynomials associated with the equilibrium distribution. A matrix of mode-correlation functions can be transformed to the complete, single-time-interval (1D) Green's function. Diagonalizing this matrix finds the eigendecays. To understand the advantages and limitation of this approach, Green's functions are calculated for a number of models of complex dynamics within a Gaussian probability distribution. Examples of non-diffusive motion, rate heterogeneity, and range heterogeneity are examined. General arguments are made that a full set of nonlinear 1D measurements is necessary to extract all the information available in a time series. However, when a process is neither dynamically Gaussian nor Markovian, they are not sufficient. In those cases, additional multidimensional measurements are needed.
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Affiliation(s)
- Stuart R Hodge
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
| | - Mark A Berg
- Department of Chemistry and Biochemistry, University of South Carolina, Columbia, South Carolina 29208, USA
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7
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Becher M, Wohlfromm T, Rössler EA, Vogel M. Molecular dynamics simulations vs field-cycling NMR relaxometry: Structural relaxation mechanisms in the glass-former glycerol revisited. J Chem Phys 2021; 154:124503. [PMID: 33810699 DOI: 10.1063/5.0048131] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
We combine field-cycling (FC) relaxometry and molecular dynamics (MD) simulations to study the rotational and translational dynamics associated with the glassy slowdown of glycerol. The 1H NMR spin-lattice relaxation rates R1(ω) probed in the FC measurements for different isotope-labelled compounds are computed from the MD trajectories for broad frequency and temperature ranges. We find high correspondence between experiment and simulation. Concerning the rotational motion, we observe that the aliphatic and hydroxyl groups show similar correlation times but different stretching parameters, while the overall reorientation associated with the structural relaxation remains largely isotropic. Additional analysis of the simulation results reveals that transitions between different molecular configurations are slow on the time scale of the structural relaxation at least at sufficiently high temperatures, indicating that glycerol rotates at a rigid entity, but the reorientation is slower for elongated than for compact conformers. The translational contribution to R1(ω) is well described by the force-free hard sphere model. At sufficiently low frequencies, universal square-root laws provide access to the molecular diffusion coefficients. In both experiment and simulation, the time scales of the rotational and translational motions show an unusually large separation, which is at variance with the Stokes-Einstein-Debye relation. To further explore this effect, we investigate the structure and dynamics on various length scales in the simulations. We observe that a prepeak in the static structure factor S(q), which is related to a local segregation of aliphatic and hydroxyl groups, is accompanied by a peak in the correlation times τ(q) from coherent scattering functions.
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Affiliation(s)
- M Becher
- Nordbayerisches NMR-Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
| | - T Wohlfromm
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstraße 6, 64289 Darmstadt, Germany
| | - E A Rössler
- Nordbayerisches NMR-Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
| | - M Vogel
- Institute of Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstraße 6, 64289 Darmstadt, Germany
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8
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Körber T, Stäglich R, Gainaru C, Böhmer R, Rössler EA. Systematic differences in the relaxation stretching of polar molecular liquids probed by dielectric vs magnetic resonance and photon correlation spectroscopy. J Chem Phys 2020; 153:124510. [DOI: 10.1063/5.0022155] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Affiliation(s)
- Thomas Körber
- Anorganische Chemie III and Nordbayerisches NMR Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Robert Stäglich
- Anorganische Chemie III and Nordbayerisches NMR Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Catalin Gainaru
- Fakultät Physik, Technische Universität Dortmund, 44221 Dortmund, Germany
| | - Roland Böhmer
- Fakultät Physik, Technische Universität Dortmund, 44221 Dortmund, Germany
| | - Ernst A. Rössler
- Anorganische Chemie III and Nordbayerisches NMR Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
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9
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Flämig M, Hofmann M, Fatkullin N, Rössler EA. NMR Relaxometry: The Canonical Case Glycerol. J Phys Chem B 2020; 124:1557-1570. [DOI: 10.1021/acs.jpcb.9b11770] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- M. Flämig
- Nordbayerisches NMR-Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
| | - M. Hofmann
- Nordbayerisches NMR-Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
| | - N. Fatkullin
- Nordbayerisches NMR-Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
- Institute of Physics, Kazan Federal University, Kremlevskaya 18, 420008 Kazan, Tatarstan, Russia
| | - E. A. Rössler
- Nordbayerisches NMR-Zentrum, Universität Bayreuth, 95440 Bayreuth, Germany
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10
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Flämig M, Hofmann M, Lichtinger A, Rössler EA. Application of proton field-cycling NMR relaxometry for studying translational diffusion in simple liquids and polymer melts. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2019; 57:805-817. [PMID: 30604576 DOI: 10.1002/mrc.4823] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 12/19/2018] [Accepted: 12/20/2018] [Indexed: 06/09/2023]
Abstract
With the availability of commercial field-cycling relaxometers together with progress of home-built instruments nuclear magnetic resonance relaxometry has gained new momentum as a method of investigating the dynamics in viscous liquids and polymer melts. The method provides the frequency dependence of the spin-lattice relaxation rate. In the case of protons, one distinguishes intramolecular and intermolecular relaxation pathways. Whereas the intramolecular contribution prevails at high frequencies and reflects rotational dynamics, the often ignored intermolecular relaxation contribution dominates at low-frequency and provides access to translational dynamics. A universal low-frequencies dispersion law holds which in pure systems allows determining the diffusion coefficient in a straightforward way. In addition, the rotational time constant is extracted from the high-frequency relaxation contribution. This is demonstrated for simple and ionic liquids and for polymer melts.
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Affiliation(s)
- Max Flämig
- Experimentalphysik and Nordbayerisches NMR-Zentrum, Universität Bayreuth, Bayreuth, Germany
| | - Marius Hofmann
- Experimentalphysik and Nordbayerisches NMR-Zentrum, Universität Bayreuth, Bayreuth, Germany
| | - Anne Lichtinger
- Experimentalphysik and Nordbayerisches NMR-Zentrum, Universität Bayreuth, Bayreuth, Germany
| | - Ernst A Rössler
- Experimentalphysik and Nordbayerisches NMR-Zentrum, Universität Bayreuth, Bayreuth, Germany
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11
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Flämig M, Hofmann M, Rössler EA. Field-cycling NMR relaxometry: the benefit of constructing master curves. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1517906] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- M. Flämig
- Experimentalphysik II, Universität Bayreuth, Bayreuth, Germany
| | - M. Hofmann
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, USA
| | - E. A. Rössler
- Experimentalphysik II, Universität Bayreuth, Bayreuth, Germany
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12
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Ladd-Parada M, Povey MJ, Vieira J, Ries ME. Fast field cycling NMR relaxometry studies of molten and cooled cocoa butter. Mol Phys 2018. [DOI: 10.1080/00268976.2018.1508784] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
| | - Megan J. Povey
- School of Food Science and Nutrition, University of Leeds, Leeds, UK
| | | | - Michael E. Ries
- School of Physics and Astronomy, University of Leeds, Leeds, UK
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13
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Affiliation(s)
- Marius Hofmann
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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14
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Pestryaev EM. Oscillating Free Induction Decay in Polymer Systems: Theoretical Analysis. POLYMER SCIENCE SERIES A 2018. [DOI: 10.1134/s0965545x18040090] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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Lozovoi A, Mattea C, Hofmann M, Saalwaechter K, Fatkullin N, Stapf S. Segmental dynamics of polyethylene-alt-propylene studied by NMR spin echo techniques. J Chem Phys 2017; 146:224901. [PMID: 29166039 DOI: 10.1063/1.4984265] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Segmental dynamics of a highly entangled melt of linear polyethylene-alt-propylene with a molecular weight of 200 kDa was studied with a novel proton nuclear magnetic resonance (NMR) approach based upon 1H → 2H isotope dilution as applied to a solid-echo build-up function ISE(t), which is constructed from the NMR spin echo signals arising from the Hahn echo (HE) and two variations of the solid-echo pulse sequence. The isotope dilution enables the separation of inter- and intramolecular contributions to this function and allows one to extract the segmental mean-squared displacements in the millisecond time range, which is hardly accessible by other experimental methods. The proposed technique in combination with time-temperature superposition yields information about segmental translation in polyethylene-alt-propylene over 6 decades in time from 10-6 s up to 1 s. The time dependence of the mean-squared displacement obtained in this time range clearly shows three regimes of power law with exponents, which are in good agreement with the tube-reptation model predictions for the Rouse model, incoherent reptation and coherent reptation regimes. The results at short times coincide with the fast-field cycling relaxometry and neutron spin echo data, yet, significantly extending the probed time range. Furthermore, the obtained data are verified as well by the use of the dipolar-correlation effect on the Hahn echo, which was developed before by the co-authors. At the same time, the amplitude ratio of the intermolecular part of the proton dynamic dipole-dipole correlation function over the intramolecular part obtained from the experimental data is not in agreement with the predictions of the tube-reptation model for the regimes of incoherent and coherent reptation.
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Affiliation(s)
- A Lozovoi
- Department of Technical Physics II, Technische Universität Ilmenau, 98684 Ilmenau, Germany
| | - C Mattea
- Department of Technical Physics II, Technische Universität Ilmenau, 98684 Ilmenau, Germany
| | - M Hofmann
- Department of Chemistry, Louisiana State University, 70803 Baton Rouge, Louisiana, USA
| | - K Saalwaechter
- Institut für Physik, Martin-Luther-Universität Halle-Wittenberg, D-06099 Halle (Saale), Germany
| | - N Fatkullin
- Institute of Physics, Kazan Federal University, Kazan 420008, Tatarstan, Russia
| | - S Stapf
- Department of Technical Physics II, Technische Universität Ilmenau, 98684 Ilmenau, Germany
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16
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Körber T, Mohamed F, Hofmann M, Lichtinger A, Willner L, Rössler EA. The Nature of Secondary Relaxations: The Case of Poly(ethylene-alt-propylene) Studied by Dielectric and Deuteron NMR Spectroscopy. Macromolecules 2017. [DOI: 10.1021/acs.macromol.6b02536] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Thomas Körber
- Experimentalphysik
II, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Fathia Mohamed
- Experimentalphysik
II, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Marius Hofmann
- Experimentalphysik
II, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Anne Lichtinger
- Experimentalphysik
II, Universität Bayreuth, 95440 Bayreuth, Germany
| | - Lutz Willner
- Institute
of Complex Systems, Forschungszentrum Jülich, D-52425 Jülich, Germany
| | - Ernst A. Rössler
- Experimentalphysik
II, Universität Bayreuth, 95440 Bayreuth, Germany
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17
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Hofmann M, Kresse B, Heymann L, Privalov AF, Willner L, Fatkullin N, Aksel N, Fujara F, Rössler EA. Dynamics of a Paradigmatic Linear Polymer: A Proton Field-Cycling NMR Relaxometry Study on Poly(ethylene–propylene). Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01906] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Hofmann
- Experimentalphysik
II, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - B. Kresse
- Institut
für Festkörperphysik, TU Darmstadt, D-64289 Darmstadt, Germany
| | - L. Heymann
- Technische
Mechanik und Strömungsmechanik, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - A. F. Privalov
- Institut
für Festkörperphysik, TU Darmstadt, D-64289 Darmstadt, Germany
| | - L. Willner
- Institute
of Complex Systems, Forschungszentrum Jülich, D-52425 Jülich, Germany
| | - N. Fatkullin
- Institute
of Physics, Kazan Federal University, Kazan 420008, Tatarstan Russia
| | - N. Aksel
- Technische
Mechanik und Strömungsmechanik, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - F. Fujara
- Institut
für Festkörperphysik, TU Darmstadt, D-64289 Darmstadt, Germany
| | - E. A. Rössler
- Experimentalphysik
II, Universität Bayreuth, D-95440 Bayreuth, Germany
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18
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Hofmann M, Kresse B, Privalov AF, Heymann L, Willner L, Aksel N, Fatkullin N, Fujara F, Rössler EA. Segmental Mean Square Displacement: Field-Cycling 1H Relaxometry vs Neutron Scattering. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01860] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- M. Hofmann
- Experimentalphysik
II, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - B. Kresse
- Institut
für Festkörperphysik, TU Darmstadt, Hochschulstrasse 6, D-64289 Darmstadt, Germany
| | - A. F. Privalov
- Institut
für Festkörperphysik, TU Darmstadt, Hochschulstrasse 6, D-64289 Darmstadt, Germany
| | - L. Heymann
- Technische
Mechanik und Strömungsmechanik, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - L. Willner
- Institute
of Complex Systems, Forschungszentrum Jülich, D-52425 Jülich, Germany
| | - N. Aksel
- Technische
Mechanik und Strömungsmechanik, Universität Bayreuth, D-95440 Bayreuth, Germany
| | - N. Fatkullin
- Institute
of Physics, Kazan Federal University, Kazan 420008, Tatarstan Russia
| | - F. Fujara
- Institut
für Festkörperphysik, TU Darmstadt, Hochschulstrasse 6, D-64289 Darmstadt, Germany
| | - E. A. Rössler
- Experimentalphysik
II, Universität Bayreuth, D-95440 Bayreuth, Germany
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