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Hajime Tanaka - One of the best experts on this subject based on the ideXlab platform.
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drastic enhancement of crystal nucleation in a molecular Liquid by its Liquid Liquid Transition
Proceedings of the National Academy of Sciences of the United States of America, 2019Co-Authors: Rei Kurita, Hajime TanakaAbstract:Crystallization is one of the most familiar and fundamental phase Transition phenomena. There is a possibility that crystallization may be enhanced by critical-like fluctuations associated with another nearby phase Transition if the order parameter of the former is coupled to that of the latter; however, the mechanism of such order parameter coupling and its generality remain elusive due to the lack of experimental studies. Here we report experimental evidence for a nontrivial coupling between crystallization and Liquid–Liquid Transition (LLT) for a molecular Liquid, triphenyl phosphite. We find that the crystal nucleation frequency is drastically enhanced by short-time preannealing near but above the spinodal temperature of LLT. By successfully separating the thermodynamic and kinetic factors governing crystal nucleation, we show that this enhancement is induced by the lowering of the crystal–Liquid interfacial energy due to the presence of critical-like order parameter fluctuations. This finding may be regarded as a fingerprint of the presence of LLT below the melting point. Thus, it may allow us not only to control the crystal nucleation frequency by LLT but also to unveil LLT hidden behind crystallization. This enhancement of nucleation frequency by critical-like fluctuations of another ordering phenomenon may be general to a variety of combinations of phase Transitions. It would provide a way to control a crystal grain structure, which is a crucial control factor of mechanical and thermal properties of crystalline materials.
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time resolved light scattering study on the kinetics of the Liquid Liquid Transition in triphenyl phosphite b
The Journal of Physical Chemistry, 2015Co-Authors: Mika Kobayashi, Ryotaro Shimizu, Hajime TanakaAbstract:There is experimental evidence suggesting the existence of a Liquid–Liquid Transition (LLT) in a single-component Liquid. However, none of this evidence is free from controversy, including the case of a molecular Liquid, triphenyl phosphite, which we study here. Furthermore, the kinetics of LLT has been largely unexplored. Here we study the phase-Transition dynamics of triphenyl phosphite in a supercooled Liquid state by means of time-resolved polarized and depolarized small-angle light scattering to clarify whether the Transition is a Liquid–Liquid Transition (LLT) or merely nanocrystal formation. A part of this study was recently reported in another of our papers [Shimizu, R.; Kobayashi, M.; Tanaka, H. Phys. Rev. Lett. 2014, 112, 125702]. A detailed analysis of our experimental results of light scattering and the comparison with heat evolution during LLT have revealed the following facts. The polarized scattering from domains has a finite (nonzero) intensity in the low-wavenumber limit, and the time evolution of its average intensity is almost proportional to the square of the heat-releasing rate. The depolarized scattering intensity monotonically increases in the process of LLT during isothermal annealing above the spinodal temperature TSD but exhibits a peak below TSD. On the basis of these results, we suggest that the primary process is LLT, whose order parameter is of a nonconserved nature, but accompanies nanocrystal formation. In the NG-type LLT, the sharp interface between Liquid II droplets and the Liquid I matrix promotes nanocrystal formation there, whereas much less nanocrystal formation is induced in the SD-type LLT due to the lack of such sharp interfaces.
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evidence of Liquid Liquid Transition in triphenyl phosphite from time resolved light scattering experiments
Physical Review Letters, 2014Co-Authors: Ryotaro Shimizu, Mika Kobayashi, Hajime TanakaAbstract:Here, we study the phase Transition kinetics in a supercooled Liquid state of triphenyl phosphite by means of time-resolved polarized and depolarized light scattering to address a long-standing controversy on its mechanism, i.e., whether the phenomenon is primarily induced by Liquid-Liquid Transition (LLT) or by nanocrystal formation. We find that the polarized scattering intensity exhibits a peak as a function of time, and its low wave number limit is nonzero for any annealing temperatures, both of which strongly indicate the nonconserved nature of an order parameter governing the Transition. We also observe evolution of depolarized scattering. Above the spinodal temperature ${T}_{\mathrm{SD}}$, the depolarized scattering intensity monotonically increases with time since it is dominated by scattering from nanocrystallites, which are continuously formed during the process. Below ${T}_{\mathrm{SD}}$, on the other hand, it exhibits a distinct peak as a function of time as the polarized scattering intensity does. This appearance of the peak suggests that dielectric tensor fluctuations responsible for the depolarized scattering mainly come from isotropic density fluctuations and not from nanocrystallites, supporting the occurrence of LLT.
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bond orientational order in Liquids towards a unified description of water like anomalies Liquid Liquid Transition glass Transition and crystallization bond orientational order in Liquids
European Physical Journal E, 2012Co-Authors: Hajime TanakaAbstract:There are at least three fundamental states of matter, depending upon temperature and pressure: gas, Liquid, and solid (crystal). These states are separated by first-order phase Transitions between them. In both gas and Liquid phases a complete translational and rotational symmetry exist, whereas in a solid phase both symmetries are broken. In intermediate phases between Liquid and solid, which include Liquid crystal and plastic crystal phases, only one of the two symmetries is preserved. Among the fundamental states of matter, the Liquid state is the most poorly understood. We argue that it is crucial for a better understanding of Liquids to recognize that a Liquid generally has the tendency to have a local structural order and its presence is intrinsic and universal to any Liquid. Such structural ordering is a consequence of many-body correlations, more specifically, bond angle correlations, which we believe are crucial for the description of the Liquid state. We show that this physical picture may naturally explain difficult unsolved problems associated with the Liquid state, such as anomalies of water-type Liquids (water, Si, Ge, ...), Liquid-Liquid Transition, Liquid-glass Transition, crystallization and quasicrystal formation, in a unified manner. In other words, we need a new order parameter representing a low local free-energy configuration, which is a bond orientational order parameter in many cases, in addition to a density order parameter for the physical description of these phenomena. Here we review our two-order-parameter model of Liquid and consider how transient local structural ordering is linked to all of the above-mentioned phenomena. The relationship between these phenomena is also discussed.
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Liquid Liquid Transition without macroscopic phase separation in a water glycerol mixture
Nature Materials, 2012Co-Authors: Kenichiro Murata, Hajime TanakaAbstract:The plausible existence of a Liquid–Liquid Transition (LLT) pre-empted by crystallization in supercooled water has long been debated. So far, indications of such a ‘hidden’ LLT have been found in nanoconfined water and in the amorphous polymorphism of ice. Now, the finding of an isocompositional LLT in a water–glycerol mixture where glycerol prevents water crystallization suggests a new link to an elusive LLT in pure water.
Sowhsin Chen - One of the best experts on this subject based on the ideXlab platform.
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some considerations on the water polymorphism and the Liquid Liquid Transition by the density behavior in the Liquid phase
Journal of Chemical Physics, 2019Co-Authors: F Mallamace, Carmelo Corsaro, Domenico Mallamace, Enza Fazio, Sowhsin ChenAbstract:The bulk Liquid water density data (ρ) are studied in a very large temperature pressure range including also the glass phases. A thorough analysis of their isobars, together with the suggestions of recent thermodynamical studies, gives evidence of two crossovers at T* and P* above which the hydrogen bond interaction is unable to arrange the tetrahedral network that is at the basis of the Liquid polymorphism giving rise to the low density Liquid (LDL). The curvatures of these isobars, as a function of T, are completely different: concave below P* (where maxima are) and convex above. In both the cases, a continuity between Liquid and glass is observed with P* as the border of the density evolution toward the two different polymorphic glasses (low and high density amorphous). The experimental data of the densities of these two glasses also show a markedly different pressure dependence. Here, on the basis of these observations in bulk water and by considering a recent study on the growth of the LDL phase, by decreasing temperature, we discuss the water Liquid-Liquid Transition and evaluate the isothermal compressibility inside the deep supercooled regime. Such a quantity shows an additional maximum that is pressure dependent that under ambient conditions agrees with a recent X-ray experiment. In particular, the present analysis suggests the presence of a Liquid-Liquid critical point located at about 180 MPa and 197 K.The bulk Liquid water density data (ρ) are studied in a very large temperature pressure range including also the glass phases. A thorough analysis of their isobars, together with the suggestions of recent thermodynamical studies, gives evidence of two crossovers at T* and P* above which the hydrogen bond interaction is unable to arrange the tetrahedral network that is at the basis of the Liquid polymorphism giving rise to the low density Liquid (LDL). The curvatures of these isobars, as a function of T, are completely different: concave below P* (where maxima are) and convex above. In both the cases, a continuity between Liquid and glass is observed with P* as the border of the density evolution toward the two different polymorphic glasses (low and high density amorphous). The experimental data of the densities of these two glasses also show a markedly different pressure dependence. Here, on the basis of these observations in bulk water and by considering a recent study on the growth of the LDL phase, by ...
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pressure effect on the boson peak in deeply cooled confined water evidence of a Liquid Liquid Transition
Physical Review Letters, 2015Co-Authors: Z H Wang, A I Kolesnikov, A Podlesnyak, Sowhsin ChenAbstract:We studied the boson peak in deeply cooled water confined in nanopores in order to examine the Liquid-Liquid Transition (LLT). Below ~180 K, the boson peaks at pressures P higher than ~3.5 kbar are evidently distinct from those at low pressures by higher mean frequencies and lower heights. Moreover, the higher-P boson peaks can be rescaled to a master curve while the lower-P boson peaks can be rescaled to a different one. Moreover, these phenomena agree with the existence of two Liquid phases with different densities and local structures and the associated LLT in the measured (P, T) region. Additionally, the P dependence of the librational band also agrees with the above conclusion.
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pressure effect on the boson peak in deeply cooled confined water evidence of a Liquid Liquid Transition
Physical Review Letters, 2015Co-Authors: Zhe Wang, A I Kolesnikov, A Podlesnyak, Kanae Ito, Sowhsin ChenAbstract:The boson peak in deeply cooled water confined in nanopores is studied to examine the Liquid-Liquid Transition (LLT). Below ∼180 K, the boson peaks at pressures P higher than ∼3.5 kbar are evidently distinct from those at low pressures by higher mean frequencies and lower heights. Moreover, the higher-P boson peaks can be rescaled to a master curve while the lower-P boson peaks can be rescaled to a different one. These phenomena agree with the existence of two Liquid phases with different densities and local structures and the associated LLT in the measured (P, T) region. In addition, the P dependence of the librational band also agrees with the above conclusion.
Pablo G Debenedetti - One of the best experts on this subject based on the ideXlab platform.
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pattern of property extrema in supercooled and stretched water models and a new correlation for predicting the stability limit of the Liquid state
Journal of Chemical Physics, 2019Co-Authors: Betul Uralcan, Pablo G Debenedetti, Folarin Latinwo, M A AnisimovAbstract:Water exhibits anomalous behavior in its supercooled region. A widely invoked hypothesis to explain supercooled water’s thermodynamic anomalies is the existence of a metastable Liquid-Liquid Transition terminating at a critical point. In this work, we analyze previously published and new simulation results for three commonly used molecular water models (ST2, TIP4P/2005, and TIP5P) that support the existence of the metastable Liquid-Liquid Transition. We demonstrate that a corresponding-states-like rescaling of pressure and temperature results in a significant degree of universality in the pattern of extrema loci of the density, isothermal compressibility, and isobaric heat capacity. We also report, for the first time, an intriguing correlation between the location of the Liquid-Liquid critical point, the rescaled locus of density extrema, and the stability limit of the Liquid state with respect to the vapor. A similar correlation is observed for two theoretical models that also exhibit a second (Liquid-Liquid) critical point, namely, the van der Waals and lattice-gas “two-structure” models. This new correlation is used to explore the stability limit of the Liquid state in simultaneously supercooled and stretched water.Water exhibits anomalous behavior in its supercooled region. A widely invoked hypothesis to explain supercooled water’s thermodynamic anomalies is the existence of a metastable Liquid-Liquid Transition terminating at a critical point. In this work, we analyze previously published and new simulation results for three commonly used molecular water models (ST2, TIP4P/2005, and TIP5P) that support the existence of the metastable Liquid-Liquid Transition. We demonstrate that a corresponding-states-like rescaling of pressure and temperature results in a significant degree of universality in the pattern of extrema loci of the density, isothermal compressibility, and isobaric heat capacity. We also report, for the first time, an intriguing correlation between the location of the Liquid-Liquid critical point, the rescaled locus of density extrema, and the stability limit of the Liquid state with respect to the vapor. A similar correlation is observed for two theoretical models that also exhibit a second (Liquid-li...
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metastable Liquid Liquid Transition in a molecular model of water
Nature, 2014Co-Authors: Jeremy C Palmer, Fausto Martelli, Athanassios Z Panagiotopoulos, Pablo G DebenedettiAbstract:A stable crystal phase and two metastable Liquid phases of the ST2 model of water exist at the same deeply supercooled condition, and the two Liquids undergo a first-order Liquid–Liquid Transition that meets stringent thermodynamic criteria. Water's anomalous physical properties become markedly enhanced upon supercooling below the freezing point and even seem to diverge towards infinity at around 228 K. Two papers in this issue use contrasting techniques to study this little-explored 'no-man's land' of water where extremely fast ice formation has prohibited measurements of the Liquid state. Jonas Sellberg et al. use femtosecond X-ray laser pulses to measure bulk Liquid water structure in droplets evaporatively cooled to 227 K. Even at this temperature some droplets remained Liquid on a millisecond timescale. Pushing this technique further can shed light on controversial scenarios that aim to describe and explain the many anomalous properties of water. Jeremy Palmer et al. use six advanced computational methods to demonstrate the existence of two metastable Liquid phases of ST2 water at the same deeply supercooled condition, undergoing a Liquid–Liquid Transition that meets stringent thermodynamic criteria and could explain the behavior of water in this regime. Liquid water’s isothermal compressibility1 and isobaric heat capacity2, and the magnitude of its thermal expansion coefficient3, increase sharply on cooling below the equilibrium freezing point. Many experimental4,5,6,7,8, theoretical9,10,11 and computational12,13 studies have sought to understand the molecular origin and implications of this anomalous behaviour. Of the different theoretical scenarios9,14,15 put forward, one posits the existence of a first-order phase Transition that involves two forms of Liquid water and terminates at a critical point located at deeply supercooled conditions9,12. Some experimental evidence is consistent with this hypothesis4,16, but no definitive proof of a Liquid–Liquid Transition in water has been obtained to date: rapid ice crystallization has so far prevented decisive measurements on deeply supercooled water, although this challenge has been overcome recently16. Computer simulations are therefore crucial for exploring water’s structure and behaviour in this regime, and have shown13,17,18,19,20,21 that some water models exhibit Liquid–Liquid Transitions and others do not. However, recent work22,23 has argued that the Liquid–Liquid Transition has been mistakenly interpreted, and is in fact a Liquid–crystal Transition in all atomistic models of water. Here we show, by studying the Liquid–Liquid Transition in the ST2 model of water24 with the use of six advanced sampling methods to compute the free-energy surface, that two metastable Liquid phases and a stable crystal phase exist at the same deeply supercooled thermodynamic condition, and that the Transition between the two Liquids satisfies the thermodynamic criteria of a first-order Transition25. We follow the rearrangement of water’s coordination shell and topological ring structure along a thermodynamically reversible path from the low-density Liquid to cubic ice26. We also show that the system fluctuates freely between the two Liquid phases rather than crystallizing. These findings provide unambiguous evidence for a Liquid–Liquid Transition in the ST2 model of water, and point to the separation of time scales between crystallization and relaxation as being crucial for enabling it.
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the Liquid Liquid Transition in supercooled st2 water a comparison between umbrella sampling and well tempered metadynamics
Faraday Discussions, 2013Co-Authors: Jeremy C Palmer, Roberto Car, Pablo G DebenedettiAbstract:We investigate the metastable phase behaviour of the ST2 water model under deeply supercooled conditions. The phase behaviour is examined using umbrella sampling (US) and well-tempered metadynamics (WT-MetaD) simulations to compute the reversible free energy surface parameterized by density and bond-orientation order. We find that free energy surfaces computed with both techniques clearly show two Liquid phases in coexistence, in agreement with our earlier US and grand canonical Monte Carlo calculations [Y. Liu, J. C. Palmer, A. Z. Panagiotopoulos and P. G. Debenedetti, J Chem Phys, 2012, 137, 214505; Y. Liu, A. Z. Panagiotopoulos and P. G. Debenedetti, J Chem Phys, 2009, 131, 104508]. While we demonstrate that US and WT-MetaD produce consistent results, the latter technique is estimated to be more computationally efficient by an order of magnitude. As a result, we show that WT-MetaD can be used to study the finite-size scaling behaviour of the free energy barrier separating the two Liquids for systems containing 192, 300 and 400 ST2 molecules. Although our results are consistent with the expected N2/3 scaling law, we conclude that larger systems must be examined to provide conclusive evidence of a first-order phase Transition and associated second critical point.
Weihua Wang - One of the best experts on this subject based on the ideXlab platform.
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evidence of Liquid Liquid Transition in glass forming la50al35ni15 melt above Liquidus temperature
Nature Communications, 2015Co-Authors: Magdalena Traico Sando, Hua Ping Zhang, Weihua Wang, Li LiuAbstract:Non-density driven Liquid-Liquid Transition has been predicted in theories, but direct experimental verification is challenging because Liquid often remains metastable at Transition temperature. Here, Xu et al. provide evidence in a lanthanum-based metallic glass above its Liquidus temperature.
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evolution of hidden localized flow during glass to Liquid Transition in metallic glass
Nature Communications, 2014Co-Authors: Zheng Wang, B A Sun, H Y Bai, Weihua WangAbstract:For glasses, the structural origin of their flow phenomena, such as elastic and plastic deformations especially the microscopic hidden flow before yield and glass-to-Liquid Transition (GLT), is unclear yet due to the lack of structural information. Here we investigate the evolution of the microscopic localized flow during GLT in a prototypical metallic glass combining with dynamical mechanical relaxations, temperature-dependent tensile experiments and stress relaxation spectra. We show that the unstable and high mobility nano-scale Liquid-like regions acting as flow units persist in the glass and can be activated by either temperature or external stress. The activation of such flow units is initially reversible and correlated with β-relaxation. As the proportion of the flow units reaches a critical percolation value, a mechanical brittle-to-ductile Transition or macroscopic GLT happens. A comprehensive picture on the hidden flow as well as its correlation with deformation maps and relaxation spectrum is proposed.
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evolution of hidden localized flow during glass to Liquid Transition in metallic glass
Nature Communications, 2014Co-Authors: Zheng Wang, Weihua WangAbstract:Glasses are known to have very slow flow behaviour on application of force, but the structural basis for this flow is currently unclear. Here Wang et al. use a dynamic mechanical analysis to study the flow phenomena in a La-based metallic glass.
Jeremy C Palmer - One of the best experts on this subject based on the ideXlab platform.
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metastable Liquid Liquid Transition in a molecular model of water
Nature, 2014Co-Authors: Jeremy C Palmer, Fausto Martelli, Athanassios Z Panagiotopoulos, Pablo G DebenedettiAbstract:A stable crystal phase and two metastable Liquid phases of the ST2 model of water exist at the same deeply supercooled condition, and the two Liquids undergo a first-order Liquid–Liquid Transition that meets stringent thermodynamic criteria. Water's anomalous physical properties become markedly enhanced upon supercooling below the freezing point and even seem to diverge towards infinity at around 228 K. Two papers in this issue use contrasting techniques to study this little-explored 'no-man's land' of water where extremely fast ice formation has prohibited measurements of the Liquid state. Jonas Sellberg et al. use femtosecond X-ray laser pulses to measure bulk Liquid water structure in droplets evaporatively cooled to 227 K. Even at this temperature some droplets remained Liquid on a millisecond timescale. Pushing this technique further can shed light on controversial scenarios that aim to describe and explain the many anomalous properties of water. Jeremy Palmer et al. use six advanced computational methods to demonstrate the existence of two metastable Liquid phases of ST2 water at the same deeply supercooled condition, undergoing a Liquid–Liquid Transition that meets stringent thermodynamic criteria and could explain the behavior of water in this regime. Liquid water’s isothermal compressibility1 and isobaric heat capacity2, and the magnitude of its thermal expansion coefficient3, increase sharply on cooling below the equilibrium freezing point. Many experimental4,5,6,7,8, theoretical9,10,11 and computational12,13 studies have sought to understand the molecular origin and implications of this anomalous behaviour. Of the different theoretical scenarios9,14,15 put forward, one posits the existence of a first-order phase Transition that involves two forms of Liquid water and terminates at a critical point located at deeply supercooled conditions9,12. Some experimental evidence is consistent with this hypothesis4,16, but no definitive proof of a Liquid–Liquid Transition in water has been obtained to date: rapid ice crystallization has so far prevented decisive measurements on deeply supercooled water, although this challenge has been overcome recently16. Computer simulations are therefore crucial for exploring water’s structure and behaviour in this regime, and have shown13,17,18,19,20,21 that some water models exhibit Liquid–Liquid Transitions and others do not. However, recent work22,23 has argued that the Liquid–Liquid Transition has been mistakenly interpreted, and is in fact a Liquid–crystal Transition in all atomistic models of water. Here we show, by studying the Liquid–Liquid Transition in the ST2 model of water24 with the use of six advanced sampling methods to compute the free-energy surface, that two metastable Liquid phases and a stable crystal phase exist at the same deeply supercooled thermodynamic condition, and that the Transition between the two Liquids satisfies the thermodynamic criteria of a first-order Transition25. We follow the rearrangement of water’s coordination shell and topological ring structure along a thermodynamically reversible path from the low-density Liquid to cubic ice26. We also show that the system fluctuates freely between the two Liquid phases rather than crystallizing. These findings provide unambiguous evidence for a Liquid–Liquid Transition in the ST2 model of water, and point to the separation of time scales between crystallization and relaxation as being crucial for enabling it.
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the Liquid Liquid Transition in supercooled st2 water a comparison between umbrella sampling and well tempered metadynamics
Faraday Discussions, 2013Co-Authors: Jeremy C Palmer, Roberto Car, Pablo G DebenedettiAbstract:We investigate the metastable phase behaviour of the ST2 water model under deeply supercooled conditions. The phase behaviour is examined using umbrella sampling (US) and well-tempered metadynamics (WT-MetaD) simulations to compute the reversible free energy surface parameterized by density and bond-orientation order. We find that free energy surfaces computed with both techniques clearly show two Liquid phases in coexistence, in agreement with our earlier US and grand canonical Monte Carlo calculations [Y. Liu, J. C. Palmer, A. Z. Panagiotopoulos and P. G. Debenedetti, J Chem Phys, 2012, 137, 214505; Y. Liu, A. Z. Panagiotopoulos and P. G. Debenedetti, J Chem Phys, 2009, 131, 104508]. While we demonstrate that US and WT-MetaD produce consistent results, the latter technique is estimated to be more computationally efficient by an order of magnitude. As a result, we show that WT-MetaD can be used to study the finite-size scaling behaviour of the free energy barrier separating the two Liquids for systems containing 192, 300 and 400 ST2 molecules. Although our results are consistent with the expected N2/3 scaling law, we conclude that larger systems must be examined to provide conclusive evidence of a first-order phase Transition and associated second critical point.