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Grzybowski A, Koperwas K, Paluch M. Role of anisotropy in understanding the molecular grounds for density scaling in dynamics of glass-forming liquids. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2024; 87:084501. [PMID: 38861964 DOI: 10.1088/1361-6633/ad569d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Accepted: 06/11/2024] [Indexed: 06/13/2024]
Abstract
Molecular Dynamics (MD) simulations of glass-forming liquids play a pivotal role in uncovering the molecular nature of the liquid vitrification process. In particular, much focus was given to elucidating the interplay between the character of intermolecular potential and molecular dynamics behaviour. This has been tried to achieve by simulating the spherical particles interacting via isotropic potential. However, when simulation and experimental data are analysed in the same way by using the density scaling approaches, serious inconsistency is revealed between them. Similar scaling exponent values are determined by analysing the relaxation times and pVT data obtained from computer simulations. In contrast, these values differ significantly when the same analysis is carried out in the case of experimental data. As discussed thoroughly herein, the coherence between results of simulation and experiment can be achieved if anisotropy of intermolecular interactions is introduced to MD simulations. In practice, it has been realized in two different ways: (1) by using the anisotropic potential of the Gay-Berne type or (2) by replacing the spherical particles with quasi-real polyatomic anisotropic molecules interacting through isotropic Lenard-Jones potential. In particular, the last strategy has the potential to be used to explore the relationship between molecular architecture and molecular dynamics behaviour. Finally, we hope that the results presented in this review will also encourage others to explore how 'anisotropy' affects remaining aspects related to liquid-glass transition, like heterogeneity, glass transition temperature, glass forming ability, etc.
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Affiliation(s)
- A Grzybowski
- Institute of Physics, University of Silesia in Katowice, 41-500 Chorzów, Poland
| | - K Koperwas
- Institute of Physics, University of Silesia in Katowice, 41-500 Chorzów, Poland
| | - M Paluch
- Institute of Physics, University of Silesia in Katowice, 41-500 Chorzów, Poland
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2
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Grzybowski A, Lowe AR, Jasiok B, Chorążewski M. Volumetric and viscosity data of selected oils analyzed in the density scaling regime. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.118728] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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3
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Liszka K, Grzybowski A, Koperwas K, Paluch M. Density Scaling of Translational and Rotational Molecular Dynamics in a Simple Ellipsoidal Model near the Glass Transition. Int J Mol Sci 2022; 23:ijms23094546. [PMID: 35562937 PMCID: PMC9103086 DOI: 10.3390/ijms23094546] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 04/15/2022] [Accepted: 04/17/2022] [Indexed: 12/03/2022] Open
Abstract
In this paper, we show that a simple anisotropic model of supercooled liquid properly reflects some density scaling properties observed for experimental data, contrary to many previous results obtained from isotropic models. We employ a well-known Gay–Berne model earlier parametrized to achieve a supercooling and glass transition at zero pressure to find the point of glass transition and explore volumetric and dynamic properties in the supercooled liquid state at elevated pressure. We focus on dynamic scaling properties of the anisotropic model of supercooled liquid to gain a better insight into the grounds for the density scaling idea that bears hallmarks of universality, as follows from plenty of experimental data collected near the glass transition for different dynamic quantities. As a result, the most appropriate values of the scaling exponent γ are established as invariants for a given anisotropy aspect ratio to successfully scale both the translational and rotational relaxation times considered as single variable functions of densityγ/temperature. These scaling exponent values are determined based on the density scaling criterion and differ from those obtained in other ways, such as the virial–potential energy correlation and the equation of state derived from the effective short-range intermolecular potential, which is qualitatively in accordance with the results yielded from experimental data analyses. Our findings strongly suggest that there is a deep need to employ anisotropic models in the study of glass transition and supercooled liquids instead of the isotropic ones very commonly exploited in molecular dynamics simulations of supercooled liquids over the last decades.
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Affiliation(s)
- Karol Liszka
- Institute of Physics, University of Silesia in Katowice, ul. 75 Pulku Piechoty 1, 41-500 Chorzow, Poland; (K.L.); (K.K.); (M.P.)
- Silesian Center for Education and Interdisciplinary Research, ul. 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
| | - Andrzej Grzybowski
- Institute of Physics, University of Silesia in Katowice, ul. 75 Pulku Piechoty 1, 41-500 Chorzow, Poland; (K.L.); (K.K.); (M.P.)
- Silesian Center for Education and Interdisciplinary Research, ul. 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
- Correspondence:
| | - Kajetan Koperwas
- Institute of Physics, University of Silesia in Katowice, ul. 75 Pulku Piechoty 1, 41-500 Chorzow, Poland; (K.L.); (K.K.); (M.P.)
- Silesian Center for Education and Interdisciplinary Research, ul. 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
| | - Marian Paluch
- Institute of Physics, University of Silesia in Katowice, ul. 75 Pulku Piechoty 1, 41-500 Chorzow, Poland; (K.L.); (K.K.); (M.P.)
- Silesian Center for Education and Interdisciplinary Research, ul. 75 Pulku Piechoty 1a, 41-500 Chorzow, Poland
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4
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Density Scaling Based Detection of Thermodynamic Regions of Complex Intermolecular Interactions Characterizing Supramolecular Structures. Sci Rep 2020; 10:9316. [PMID: 32518282 PMCID: PMC7283260 DOI: 10.1038/s41598-020-66244-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 04/06/2020] [Indexed: 11/17/2022] Open
Abstract
In this paper, applying the density scaling idea to an associated liquid 4-methyl-2-pentanol used as an example, we identify different pressure-volume-temperature ranges within which molecular dynamics is dominated by either complex H-bonded networks most probably leading to supramolecular structures or non-specific intermolecular interactions like van der Waals forces. In this way, we show that the density scaling law for molecular dynamics near the glass transition provides a sensitive tool to detect thermodynamic regions characterized by intermolecular interactions of different type and complexity for a given material in the wide pressure-volume-temperature domain even if its typical form with constant scaling exponent is not obeyed. Moreover, we quantify the observed decoupling between dielectric and mechanical relaxations of the material in the density scaling regime. The suggested methods of analyses and their interpretations open new prospects for formulating models based on proper effective intermolecular potentials describing physicochemical phenomena near the glass transition.
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5
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Koperwas K, Grzybowski A, Paluch M. The effect of molecular architecture on the physical properties of supercooled liquids studied by MD simulations: Density scaling and its relation to the equation of state. J Chem Phys 2019; 150:014501. [PMID: 30621418 DOI: 10.1063/1.5050330] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Theoretical concepts in condensed matter physics are typically verified and also developed by exploiting computer simulations mostly in simple models. Predictions based on these usually isotropic models are often at odds with measurement results obtained for real materials. One of the examples is an intriguing problem within the density scaling idea that has attracted attention in recent decades due to its hallmarks of universality, i.e., the fact that the difference between the density scaling exponent and the exponent of the equation of state is observed for real materials, whereas it has not been reported for the model system. In this paper, we use new model molecules of simple but anisotropic architecture to study the effect of molecular anisotropy on the dynamic and thermodynamic properties of the system. We identify the applicable range of intermolecular interactions for a given physical process, and then we explain the reason for observed differences between the behavior of the model and real systems. It demonstrates that the new model systems open broad perspectives for simulation and theoretical research, for example, into unifying concepts in the glass transition physics.
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Affiliation(s)
- K Koperwas
- Institute of Physics, University of Silesia in Katowice, 75 Pułku Piechoty 1, 41-500 Chorzów, Poland
| | - A Grzybowski
- Institute of Physics, University of Silesia in Katowice, 75 Pułku Piechoty 1, 41-500 Chorzów, Poland
| | - M Paluch
- Institute of Physics, University of Silesia in Katowice, 75 Pułku Piechoty 1, 41-500 Chorzów, Poland
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6
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López ER, Fandiño O, Cabaleiro D, Lugo L, Fernández J. Determination of derived volumetric properties and heat capacities at high pressures using two density scaling based equations of state. Application to dipentaerythritol hexa(3,5,5-trimethylhexanoate). Phys Chem Chem Phys 2018; 20:3531-3542. [DOI: 10.1039/c7cp07180a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Scaling based EoSs describe the complex behavior of derived properties for broad temperature and pressure ranges from diPEiC9 experimental densities.
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Affiliation(s)
- E. R. López
- Laboratorio de Propiedades Termofísicas
- Grupo NaFoMat
- Departamento de Física Aplicada
- Universidade de Santiago de Compostela
- E-15782 Santiago de Compostela
| | - O. Fandiño
- Laboratorio de Propiedades Termofísicas
- Grupo NaFoMat
- Departamento de Física Aplicada
- Universidade de Santiago de Compostela
- E-15782 Santiago de Compostela
| | - D. Cabaleiro
- Departamento de Física Aplicada
- Facultade de Ciencias
- Universidade de Vigo
- E-36310 Vigo
- Spain
| | - L. Lugo
- Laboratorio de Propiedades Termofísicas
- Grupo NaFoMat
- Departamento de Física Aplicada
- Universidade de Santiago de Compostela
- E-15782 Santiago de Compostela
| | - J. Fernández
- Laboratorio de Propiedades Termofísicas
- Grupo NaFoMat
- Departamento de Física Aplicada
- Universidade de Santiago de Compostela
- E-15782 Santiago de Compostela
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7
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Jedrzejowska A, Grzybowski A, Paluch M. In search of invariants for viscous liquids in the density scaling regime: investigations of dynamic and thermodynamic moduli. Phys Chem Chem Phys 2017; 19:18348-18355. [PMID: 28678273 DOI: 10.1039/c7cp01144j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In this paper, we report the nontrivial results of our investigations of dynamic and thermodynamic moduli in search of invariants for viscous liquids in the density scaling regime by using selected supercooled van der Waals liquids as representative materials. Previously, the dynamic modulus Mp-T (defined in the pressure-temperature representation by the ratio of isobaric activation energy and activation volume) as well as the ratio BT/Mp-T (where BT is the thermodynamic modulus defined as the inverse isothermal compressibility) have been suggested as some kinds of material constants. We have established that they are not valid in the explored wide range of temperatures T over a dozen decades of structural relaxation times τ. The temperature dependences of Mp-T and BT/Mp-T have been elucidated by comparison with the well-known measure of the relative contribution of temperature and density fluctuations to molecular dynamics near the glass transition, i.e., the ratio of isochoric and isobaric activation energies. Then, we have implemented an idea to transform the definition of the dynamic modulus Mp-T from the p-T representation to the V-T one. This idea relied on the disentanglement of combined temperature and density fluctuations involved in isobaric parameters and has resulted in finding an invariant for viscous liquids in the density scaling regime, which is the ratio of thermodynamic and dynamic moduli, BT/MV-T. In this way, we have constituted a characteristic of thermodynamics and molecular dynamics, which remains unchanged in the supercooled liquid state for a given material, the molecular dynamics of which obeys the power density scaling law.
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Affiliation(s)
- Agnieszka Jedrzejowska
- Institute of Physics, University of Silesia in Katowice, Uniwersytecka 4, 40-007 Katowice, Poland.
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8
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Ransom TC, Oliver WF. Glass Transition Temperature and Density Scaling in Cumene at Very High Pressure. PHYSICAL REVIEW LETTERS 2017; 119:025702. [PMID: 28753339 DOI: 10.1103/physrevlett.119.025702] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Indexed: 06/07/2023]
Abstract
We present a new method that allows direct measurements of the glass transition temperature T_{g} at pressures up to 4.55 GPa in the glass-forming liquid cumene (isopropylbenzene). This new method uses a diamond anvil cell and can measure T_{g} at pressures of 10 GPa or greater. Measuring T_{g} at the glass→liquid transition involves monitoring the disappearance of pressure gradients initially present in the glass, but also takes advantage of the large increase in the volume expansion coefficient α_{p} at T_{g} as the supercooled or superpressed liquid is entered. Accurate T_{g}(P) values in cumene allow us to show that density scaling holds along this isochronous line up to pressures much higher than any previous study, corresponding to a density increase of 29%. Our results for cumene over this huge compression range yield ρ^{γ}/T=C, where C is a constant and where γ=4.77±0.02 for this nonassociated glass-forming system. Finally, high-pressure cumene viscosity data from the literature taken at much lower pressures and at several different temperatures, corresponding to a large dynamic range of nearly 13 orders of magnitude, are shown to superimpose on a plot of η vs ρ^{γ}/T for the same value of γ.
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Affiliation(s)
- T C Ransom
- Naval Research Laboratory, Chemistry Division, Code 6100, Washington DC 20375-5342, USA
- Physics Department, University of Arkansas, Fayetteville, Arkansas 72701, USA
| | - W F Oliver
- Physics Department, University of Arkansas, Fayetteville, Arkansas 72701, USA
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9
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Prasad S, Chakravarty C. Solvation of LiCl in model liquids with high to low hydrogen bond strengths. J Chem Phys 2017. [DOI: 10.1063/1.4982828] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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10
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Shrivastav G, Agarwal M, Chakravarty C, Kashyap HK. Thermodynamic regimes over which homologous alkane fluids can be treated as simple liquids. J Mol Liq 2017. [DOI: 10.1016/j.molliq.2017.01.085] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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11
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Activation volume of selected liquid crystals in the density scaling regime. Sci Rep 2017; 7:42174. [PMID: 28181530 PMCID: PMC5299607 DOI: 10.1038/srep42174] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 01/06/2017] [Indexed: 01/20/2023] Open
Abstract
In this paper, we demonstrate and thoroughly analyze the activation volumetric properties of selected liquid crystals in the nematic and crystalline E phases in comparison with those reported for glass-forming liquids. In the analysis, we have employed and evaluated two entropic models (based on either total or configurational entropies) to describe the longitudinal relaxation times of the liquid crystals in the density scaling regime. In this study, we have also exploited two equations of state: volumetric and activation volumetric ones. As a result, we have established that the activation volumetric properties of the selected liquid crystals are quite opposite to such typical properties of glass-forming materials, i.e., the activation volume decreases and the isothermal bulk modulus increases when a liquid crystal is isothermally compressed. Using the model based on the configurational entropy, we suggest that the increasing pressure dependences of the activation volume in isothermal conditions and the negative curvature of the pressure dependences of isothermal longitudinal relaxation times can be related to the formation of antiparallel doublets in the examined liquid crystals. A similar pressure effect on relaxation dynamics may be also observed for other material groups in case of systems, the molecules of which form some supramolecular structures.
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12
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Grzybowska K, Capaccioli S, Paluch M. Recent developments in the experimental investigations of relaxations in pharmaceuticals by dielectric techniques at ambient and elevated pressure. Adv Drug Deliv Rev 2016; 100:158-82. [PMID: 26705851 DOI: 10.1016/j.addr.2015.12.008] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Revised: 12/05/2015] [Accepted: 12/09/2015] [Indexed: 10/22/2022]
Abstract
In recent years, there is a growing interest in improving the physicochemical stability of amorphous pharmaceutical solids due to their very promising applications to manufacture medicines characterized by a better water solubility, and consequently by a higher dissolution rate than those of their crystalline counterparts. In this review article, we show that the molecular mobility investigated both in the supercooled liquid and glassy states is the crucial factor required to understand molecular mechanisms that govern the physical stability of amorphous drugs. We demonstrate that pharmaceuticals can be thoroughly examined by means of the broadband dielectric spectroscopy, which is a very useful experimental technique to explore different relaxation processes and crystallization kinetics as well. Such studies conducted in the wide temperature and pressure ranges provide data needed in searching correlations between properties of molecular dynamics and crystallization process, which are aimed at developing effective and efficient methods for stabilizing amorphous drugs.
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13
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Masiewicz E, Grzybowski A, Grzybowska K, Pawlus S, Pionteck J, Paluch M. Adam-Gibbs model in the density scaling regime and its implications for the configurational entropy scaling. Sci Rep 2015; 5:13998. [PMID: 26365623 PMCID: PMC4568462 DOI: 10.1038/srep13998] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Accepted: 07/31/2015] [Indexed: 11/15/2022] Open
Abstract
To solve a long-standing problem of condensed matter physics with determining a proper description of the thermodynamic evolution of the time scale of molecular dynamics near the glass transition, we have extended the well-known Adam-Gibbs model to describe the temperature-volume dependence of structural relaxation times, τα(T, V). We also employ the thermodynamic scaling idea reflected in the density scaling power law, τα = f(T−1V−γ), recently acknowledged as a valid unifying concept in the glass transition physics, to differentiate between physically relevant and irrelevant attempts at formulating the temperature-volume representations of the Adam-Gibbs model. As a consequence, we determine a straightforward relation between the structural relaxation time τα and the configurational entropy SC, giving evidence that also SC(T, V) = g(T−1V−γ) with the exponent γ that enables to scale τα(T, V). This important findings have meaningful implications for the connection between thermodynamics and molecular dynamics near the glass transition, because it implies that τα can be scaled with SC.
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Affiliation(s)
- Elżbieta Masiewicz
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland.,Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
| | - Andrzej Grzybowski
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland.,Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
| | - Katarzyna Grzybowska
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland.,Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
| | - Sebastian Pawlus
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland.,Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
| | - Jürgen Pionteck
- Leibniz Institute of Polymer Research Dresden, Hohe Str. 6, D-01069 Dresden, Germany
| | - Marian Paluch
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland.,Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
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14
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Chorążewski M, Grzybowski A, Paluch M. Isobaric Thermal Expansion of Compressed 1,4-Dichlorobutane and 1-Bromo-4-chlorobutane: Transitiometric Results and a Novel Application of the General Density Scaling-Based Equation of State. Ind Eng Chem Res 2015. [DOI: 10.1021/acs.iecr.5b00953] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mirosław Chorążewski
- Institute
of Chemistry, University of Silesia, Szkolna 9, 40-006 Katowice, Poland
| | - Andrzej Grzybowski
- Institute
of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
| | - Marian Paluch
- Institute
of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
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15
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Grzybowska K, Grzybowski A, Pawlus S, Pionteck J, Paluch M. Role of entropy in the thermodynamic evolution of the time scale of molecular dynamics near the glass transition. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 91:062305. [PMID: 26172717 DOI: 10.1103/physreve.91.062305] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Indexed: 06/04/2023]
Abstract
In this paper, we investigate how changes in the system entropy influence the characteristic time scale of the system molecular dynamics near the glass transition. Independently of any model of thermodynamic evolution of the time scale, against some previous suppositions, we show that the system entropy S is not sufficient to govern the time scale defined by structural relaxation time τ. In the density scaling regime, we argue that the decoupling between τ and S is a consequence of different values of the scaling exponents γ and γ(S) in the density scaling laws, τ=f(ρ(γ)/T) and S=h(ρ(γ(S))/T), where ρ and T denote density and temperature, respectively. It implies that the proper relation between τ and S requires supplementing with a density factor, u(ρ), i.e., τ=g(u(ρ)w(S)). This meaningful finding additionally demonstrates that the density scaling idea can be successfully used to separate physically relevant contributions to the time scale of molecular dynamics near the glass transition. The relation reported by us between τ and S constitutes a general pattern based on nonconfigurational quantities for describing the thermodynamic evolution of the characteristic time scale of molecular dynamics near the glass transition in the density scaling regime, which is a promising alternative to the approaches based as the Adam-Gibbs model on the configurational entropy that is difficult to evaluate in the entire thermodynamic space. As an example, we revise the Avramov entropic model of the dependence τ(T,ρ), giving evidence that its entropic basis has to be extended by the density dependence of the maximal energy barrier for structural relaxation. We also discuss the excess entropy S(ex), the density scaling of which is found to mimic the density scaling of the total system entropy S.
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Affiliation(s)
- K Grzybowska
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
| | - A Grzybowski
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
| | - S Pawlus
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
| | - J Pionteck
- Leibniz Institute of Polymer Research Dresden, Hohe Strasse 6, D-01069 Dresden, Germany
| | - M Paluch
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research, 75 Pułku Piechoty 1A, 41-500 Chorzów, Poland
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16
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Delage-Santacreu S, Galliero G, Hoang H, Bazile JP, Boned C, Fernandez J. Thermodynamic scaling of the shear viscosity of Mie n-6 fluids and their binary mixtures. J Chem Phys 2015; 142:174501. [DOI: 10.1063/1.4919296] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Stephanie Delage-Santacreu
- Laboratoire de Mathématiques et leurs Applications (UMR-5142 with CNRS), Université de Pau et des Pays de l’Adour, BP 1155, F-64013 PAU Cedex, France
| | - Guillaume Galliero
- Laboratoire des Fluides Complexes et leurs Reservoirs (UMR-5150 with CNRS and TOTAL), Université de Pau et des Pays de l’Adour, BP 1155, F-64013 PAU Cedex, France
| | - Hai Hoang
- Laboratoire des Fluides Complexes et leurs Reservoirs (UMR-5150 with CNRS and TOTAL), Université de Pau et des Pays de l’Adour, BP 1155, F-64013 PAU Cedex, France
| | - Jean-Patrick Bazile
- Laboratoire des Fluides Complexes et leurs Reservoirs (UMR-5150 with CNRS and TOTAL), Université de Pau et des Pays de l’Adour, BP 1155, F-64013 PAU Cedex, France
| | - Christian Boned
- Laboratoire des Fluides Complexes et leurs Reservoirs (UMR-5150 with CNRS and TOTAL), Université de Pau et des Pays de l’Adour, BP 1155, F-64013 PAU Cedex, France
| | - Josefa Fernandez
- Laboratorio de Propiedades Termofisicas, Universidade Santiago de Compostela, Campus Vida, E-15782 Santiago de Compostela, Spain
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17
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Wojnarowska Z, Paluch M. Recent progress on dielectric properties of protic ionic liquids. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:073202. [PMID: 25634823 DOI: 10.1088/0953-8984/27/7/073202] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Protic ionic liquids (PILs) are key materials for a wide range of emerging technologies. In particular, these systems have long been envisioned as promising candidates for fuel cells. Therefore, in recent years special attention has been devoted to thorough studies of these compounds. Amongst others, dielectric properties of PILs at ambient and elevated pressure have become the subject of intense research. The reason for this lies in the role of broadband dielectric spectroscopy in recognizing the conductivity mechanism in protic ionic systems. In this paper, we summarize the dielectric results of various PILs reflecting recent advances in this field.
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Affiliation(s)
- Zaneta Wojnarowska
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
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18
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Ribeiro MCC, Pádua AAH, Gomes MFC. Glass transition of ionic liquids under high pressure. J Chem Phys 2014; 140:244514. [DOI: 10.1063/1.4885361] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
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19
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Prasad S, Chakravarty C. Onset of simple liquid behaviour in modified water models. J Chem Phys 2014; 140:164501. [DOI: 10.1063/1.4870823] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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20
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Grzybowski A, Koperwas K, Paluch M. Equation of state in the generalized density scaling regime studied from ambient to ultra-high pressure conditions. J Chem Phys 2014; 140:044502. [DOI: 10.1063/1.4861907] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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21
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Chorążewski M, Grzybowski A, Paluch M. The complex, non-monotonic thermal response of the volumetric space of simple liquids. Phys Chem Chem Phys 2014; 16:19900-8. [PMID: 25117028 DOI: 10.1039/c4cp02350a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We show that a non-monotonic solution of the equation ∂αp(p,T)/∂T = 0 divides the phase diagram of simple liquids into two parts.
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Affiliation(s)
- M. Chorążewski
- Institute of Chemistry
- University of Silesia
- 40-006 Katowice, Poland
| | - A. Grzybowski
- Institute of Physics
- University of Silesia
- 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research
- 41-500 Chorzów, Poland
| | - M. Paluch
- Institute of Physics
- University of Silesia
- 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research
- 41-500 Chorzów, Poland
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22
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Wojnarowska Z, Jarosz G, Grzybowski A, Pionteck J, Jacquemin J, Paluch M. On the scaling behavior of electric conductivity in [C4mim][NTf2]. Phys Chem Chem Phys 2014; 16:20444-50. [DOI: 10.1039/c4cp02253j] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
In this work we examine, for the first time, the molar conductivity behavior of the deeply supercooled room temperature ionic liquid [C4mim][NTf2] in the temperature, pressure and volume thermodynamic space in terms of density scaling regime (TVγ)−1 combined with the equation of state (EOS).
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Affiliation(s)
- Z. Wojnarowska
- Institute of Physics
- University of Silesia
- 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research
- 41-500 Chorzów, Poland
| | - G. Jarosz
- Institute of Physics
- University of Silesia
- 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research
- 41-500 Chorzów, Poland
| | - A. Grzybowski
- Institute of Physics
- University of Silesia
- 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research
- 41-500 Chorzów, Poland
| | - J. Pionteck
- Leibniz Institute of Polymer Research Dresden
- D-01069 Dresden, Germany
| | - J. Jacquemin
- The School of Chemistry and Chemical Engineering/QUILL Research Centre
- Queen’s University of Belfast
- David Keir Building
- Belfast BT9 5AG, UK
| | - M. Paluch
- Institute of Physics
- University of Silesia
- 40-007 Katowice, Poland
- Silesian Center for Education and Interdisciplinary Research
- 41-500 Chorzów, Poland
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23
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Grzybowski A, Koperwas K, Kolodziejczyk K, Grzybowska K, Paluch M. Spatially Heterogeneous Dynamics in the Density Scaling Regime: Time and Length Scales of Molecular Dynamics near the Glass Transition. J Phys Chem Lett 2013; 4:4273-4278. [PMID: 26296178 DOI: 10.1021/jz402060x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Affiliation(s)
- A Grzybowski
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
| | - K Koperwas
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
| | - K Kolodziejczyk
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
| | - K Grzybowska
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
| | - M Paluch
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
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24
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Koperwas K, Grzybowski A, Grzybowska K, Wojnarowska Z, Sokolov AP, Paluch M. Effect of temperature and density fluctuations on the spatially heterogeneous dynamics of glass-forming Van der Waals liquids under high pressure. PHYSICAL REVIEW LETTERS 2013; 111:125701. [PMID: 24093275 DOI: 10.1103/physrevlett.111.125701] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Indexed: 06/02/2023]
Abstract
In this Letter, we show how temperature and density fluctuations affect the spatially heterogeneous dynamics at ambient and elevated pressures. By using high-pressure experimental data for van der Waals liquids, we examine contributions of the temperature and density fluctuations to the dynamics heterogeneity. We show that the dynamic heterogeneity decreases significantly with increasing pressure at a constant structural relaxation time (isochronal condition), while the broadening of the relaxation spectrum remains constant. This observation questions the relationship between spectral broadening and dynamic heterogeneity.
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Affiliation(s)
- K Koperwas
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
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25
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Shell MS. Systematic coarse-graining of potential energy landscapes and dynamics in liquids. J Chem Phys 2013; 137:084503. [PMID: 22938246 DOI: 10.1063/1.4746391] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Recent efforts have shown that the dynamic properties of a wide class of liquids can be mapped onto semi-universal scaling laws and constitutive relations that are motivated by thermodynamic analyses of much simpler models. In particular, it has been found that many systems exhibit dynamics whose behavior in state space closely follows that of soft-sphere particles interacting through an inverse power repulsion. In the present work, we show that a recently developed coarse-graining theory provides a natural way to understand how arbitrary liquids can be mapped onto effective soft-sphere models and hence how one might potentially be able to extract underlying dynamical scaling laws. The theory is based on the relative entropy, an information metric that quantifies how well a soft-sphere approximation to a liquid's multidimensional potential energy landscape performs. We show that optimization of the relative entropy not only enables one to extract effective soft-sphere potentials that suggest an inherent scaling of thermodynamic and dynamic properties in temperature-density space, but that also has rather interesting connections to excess entropy based theories of liquid dynamics. We apply the approach to a binary mixture of Lennard-Jones particles, and show that it gives effective soft-sphere scaling laws that well-describe the behavior of the diffusion constants. Our results suggest that the relative entropy formalism may be useful for "perturbative" type theories of dynamics, offering a general strategy for systematically connecting complex energy landscapes to simpler reference ones with better understood dynamic behavior.
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Affiliation(s)
- M Scott Shell
- Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, California 93106-5080, USA.
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26
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Koperwas K, Grzybowski A, Grzybowska K, Wojnarowska Z, Pionteck J, Sokolov AP, Paluch M. Pressure coefficient of the glass transition temperature in the thermodynamic scaling regime. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 86:041502. [PMID: 23214586 DOI: 10.1103/physreve.86.041502] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2012] [Indexed: 06/01/2023]
Abstract
We report that the pressure coefficient of the glass transition temperature, dT(g)/dp, which is commonly used to determine the pressure sensitivity of the glass transition temperature T(g), can be predicted in the thermodynamic scaling regime. We show that the equation derived from the isochronal condition combined with the well-known scaling, TV(γ) = const, predicts successfully values of dT(g)/dp for a variety of glass-forming systems, including van der Waals liquids, polymers, and ionic liquids.
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Affiliation(s)
- K Koperwas
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
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27
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Masiewicz E, Grzybowski A, Sokolov AP, Paluch M. Temperature-Volume Entropic Model for Viscosities and Structural Relaxation Times of Glass Formers. J Phys Chem Lett 2012; 3:2643-2648. [PMID: 26295885 DOI: 10.1021/jz301168c] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this Letter, an entropic model recently formulated by Mauro et al. for the temperature dependence of viscosity in glass-forming materials is generalized to describe the temperature-volume dependences of viscosities and structural relaxation times near the glass transition. It is found that the generalization shows limitations of its temperature precursor. The extended model describes well the structural dielectric relaxation times τα(T,V) of supercooled van der Waals liquids. The obtained results are discussed in the context of the thermodynamic scaling law for molecular dynamics of viscous systems.
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Affiliation(s)
- E Masiewicz
- †Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
| | - A Grzybowski
- †Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
| | - A P Sokolov
- ‡Department of Chemistry, University of Tennessee Knoxville, Tennessee 37996, United States
| | - M Paluch
- †Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland
- ‡Department of Chemistry, University of Tennessee Knoxville, Tennessee 37996, United States
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28
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Grzybowski A, Koperwas K, Paluch M. Scaling of volumetric data in model systems based on the Lennard-Jones potential. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 86:031501. [PMID: 23030917 DOI: 10.1103/physreve.86.031501] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 07/22/2012] [Indexed: 06/01/2023]
Abstract
The crucial problem for better understanding the nature of glass transition and related relaxation phenomena is to find proper interrelations between the molecular dynamics and thermodynamics of viscous systems. To make progress towards this goal the recently observed density scaling of viscous liquid dynamics has been very intensively and successfully studied in the past few years. However, previous attempts at related scaling of volumetric data yielded results inconsistent with those found from the density scaling of molecular dynamics. In this paper, we show that volumetric data obtained from simulations in simple molecular models based on the Lennard-Jones (LJ) potential, such as the Kob-Andersen binary LJ liquid, its repulsive inverse power-law version, and the Lewis-Wahnström o-terphenyl model, can be scaled by using the same value of the exponent, which scales dynamic quantities and is directly related to the exponent of the repulsive inverse power law that underlies short-range approximations of the LJ potential.
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Affiliation(s)
- A Grzybowski
- Institute of Physics, University of Silesia, Uniwersytecka 4, 40-007 Katowice, Poland.
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29
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Affiliation(s)
- M. D. Ediger
- Department of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Peter Harrowell
- School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia
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30
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Swiety-Pospiech A, Wojnarowska Z, Pionteck J, Pawlus S, Grzybowski A, Hensel-Bielowka S, Grzybowska K, Szulc A, Paluch M. High pressure study of molecular dynamics of protic ionic liquid lidocaine hydrochloride. J Chem Phys 2012; 136:224501. [DOI: 10.1063/1.4727885] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [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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López ER, Pensado AS, Fernández J, Harris KR. On the density scaling of pVT data and transport properties for molecular and ionic liquids. J Chem Phys 2012; 136:214502. [DOI: 10.1063/1.4720070] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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32
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Papathanassiou AN, Sakellis I, Grammatikakis J, Roland CM. The role of the isothermal bulk modulus in the molecular dynamics of super-cooled liquids. J Chem Phys 2011; 135:244508. [PMID: 22225170 DOI: 10.1063/1.3666008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Elastic models imply that the energy expended for a flow event in ultra-viscous matter coincides with the elastic work required for deforming and re-arranging the environment of the moving entity. This is quite promising for explaining the strong non-Arrhenius behavior of dynamic quantities of fragile super-cooled liquids. We argue that the activation volume obtained from dielectric relaxation and light-scattering experiments for super-cooled liquids should scale with the Gibbs free energy of activation, with a proportionality constant determined by the isothermal bulk modulus and its pressure derivative, as described by an earlier thermodynamic elastic model. For certain super-cooled liquids the bulk compression transpiring in the local environment, as governed by the isothermal bulk modulus, play a significant role in the reorientational dynamics, with far-field density fluctuations and volume changes avoided by shear deformation.
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33
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Brańka AC, Heyes DM, Rickayzen G. Pair force distributions in simple fluids. J Chem Phys 2011; 135:164507. [PMID: 22047252 DOI: 10.1063/1.3653942] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Analytic expressions are derived for the frequency distribution, P(f), of pair forces, f, and those of their α-Cartesian component, f(α), or P(f(α)), for some typical model simple fluids, expressed in terms of the radial distribution function and known constants. For strongly repulsive inverse power (IP), exponential and Yukawa purely repulsive potentials, P(f) diverges at the origin approximately as ∼f(-1), but with different limiting analytic forms. P(f(α)) is also shown to diverge as ∼f(-1) as f → 0 for the IP fluid. For the Lennard-Jones potential fluid, P(f) is finite for all f ≥ 0 but has two singularities for negative f, corresponding to the zero force limit (i.e., f → 0(-)) and the point of inflection in the potential. The corresponding component force distribution is singular as f(α) → 0 from both positive and negative force sides. The large force limit of P(f), which originates from the close neighbor interactions, is nearly exponential for the IP and LJ fluids, as is also found for granular materials. A more complete picture of force distributions in off-lattice particulate systems as a function of force law and state point (particularly the extent of "thermalization" of the particles) is provided.
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Affiliation(s)
- A C Brańka
- Institute of Molecular Physics, Polish Academy of Sciences, M. Smoluchowskiego 17, 60-179 Poznań, Poland.
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34
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Ribeiro MCC, Scopigno T, Ruocco G. Computer simulation study of thermodynamic scaling of dynamics of 2Ca(NO3)2·3KNO3. J Chem Phys 2011; 135:164510. [DOI: 10.1063/1.3656872] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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35
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Pawlus S, Paluch M, Grzybowski A. Communication: Thermodynamic scaling of the Debye process in primary alcohols. J Chem Phys 2011; 134:041103. [PMID: 21280678 DOI: 10.1063/1.3540636] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The molecular dynamics of hydrogen-bonded liquids usually does not satisfy the thermodynamic scaling. However, very recently, two opposite conclusions about validity of thermodynamical scaling in monohydroxy alcohol, 2-ethyl-1-hexanol, were presented by Reiser et al. [J. Chem. Phys. 132, 181101 (2010)] and Fragiadakis et al. [J. Chem. Phys. 132, 144505 (2010)]. In this communication we present new experimental results that can explain this ostensible contradiction.
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Affiliation(s)
- Sebastian Pawlus
- Institute of Physics, University of Silesia, Uniwersytecka 4, Katowice 40-007, Poland.
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36
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Grzybowski A, Grzybowska K, Paluch M, Swiety A, Koperwas K. Density scaling in viscous systems near the glass transition. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 83:041505. [PMID: 21599167 DOI: 10.1103/physreve.83.041505] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2010] [Revised: 03/08/2011] [Indexed: 05/30/2023]
Abstract
In this paper, a general equation of state (EOS) valid for fluids in the vicinity of the glass transition is derived on the basis of its isothermal precursor. This EOS is able to predict the density scaling of both isobaric and isothermal PVT data and it explicitly involves the scaling exponent γ(EOS), which is most likely straightforwardly related to the exponent of the inverse power law of some effective potential valid for viscous systems. This EOS and the density scaling are very successfully tested for representatives of several material classes (van der Waals liquids, polymer melts, ionic liquids, and even strongly hydrogen-bonded systems). Additionally, if the thermodynamic scaling of primary relaxation times can be achieved with the scaling exponent γ for a given material, then the value γ(EOS) found from fitting its PVT data to the EOS enables us to evaluate the value γ, which is always considerably smaller than γ(EOS).
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Affiliation(s)
- A Grzybowski
- Institute of Physics, Silesian University, Uniwersytecka 4, PL-40-007 Katowice, Poland.
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