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Eduardo Sanz - One of the best experts on this subject based on the ideXlab platform.

  • Interfacial Free Energy of a liquid solid interface its change with curvature
    Journal of Chemical Physics, 2019
    Co-Authors: Montero P De Hijes, Jorge R Espinosa, Eduardo Sanz, Carlos Vega
    Abstract:

    We analyze the changes in the Interfacial Free Energy between a spherical solid cluster and a fluid due to the change of the radius of the solid. Interfacial Free energies from nucleation studies using the seeding technique for four different systems, being hard spheres, Lennard-Jones, and two models of water (mW and TIP4P/ICE), were plotted as a function of the inverse of the radius of the solid cluster. In all cases, the Interfacial Free Energy was a linear function of the inverse of the radius of the solid cluster and this is consistent with Tolman’s equation. This linear behavior is shown not only in isotherms but also along isobars. The effect of curvature on the Interfacial Free Energy is more pronounced in water, followed by hard spheres, and smaller for Lennard-Jones particles. We show that it is possible to estimate nucleation rates of Lennard-Jones particles at different pressures by using information from simple NpT simulations and taking into account the variation of the Interfacial Free Energy with the radius of the solid cluster. Neglecting the effects of the radius on the Interfacial Free Energy (capillarity approximation) leads to incorrect values of the nucleation rate. For the Lennard-Jones system, the homogeneous nucleation curve is not parallel to the melting curve as was found for water in previous work. This is due to the increase in the Interfacial Free Energy along the coexistence curve as the pressure increases. This work presents a simple and relatively straightforward way to approximately estimate nucleation rates.We analyze the changes in the Interfacial Free Energy between a spherical solid cluster and a fluid due to the change of the radius of the solid. Interfacial Free energies from nucleation studies using the seeding technique for four different systems, being hard spheres, Lennard-Jones, and two models of water (mW and TIP4P/ICE), were plotted as a function of the inverse of the radius of the solid cluster. In all cases, the Interfacial Free Energy was a linear function of the inverse of the radius of the solid cluster and this is consistent with Tolman’s equation. This linear behavior is shown not only in isotherms but also along isobars. The effect of curvature on the Interfacial Free Energy is more pronounced in water, followed by hard spheres, and smaller for Lennard-Jones particles. We show that it is possible to estimate nucleation rates of Lennard-Jones particles at different pressures by using information from simple NpT simulations and taking into account the variation of the Interfacial Free energ...

  • Interfacial Free Energy as the key to the pressure induced deceleration of ice nucleation
    Physical Review Letters, 2016
    Co-Authors: Jorge R Espinosa, Carlos Vega, Chantal Valeriani, Alberto Zaragoza, P Rosalespelaez, Caridad Navarro, Eduardo Sanz
    Abstract:

    : The avoidance of water Freezing is the holy grail in the cryopreservation of biological samples, food, and organs. Fast cooling rates are used to beat ice nucleation and avoid cell damage. This strategy can be enhanced by applying high pressures to decrease the nucleation rate, but the physics behind this procedure has not been fully understood yet. We perform computer experiments to investigate ice nucleation at high pressures consisting in embedding ice seeds in supercooled water. We find that the slowing down of the nucleation rate is mainly due to an increase of the ice I-water Interfacial Free Energy with pressure. Our work also clarifies the molecular mechanism of ice nucleation for a wide pressure range. This study is not only relevant to cryopreservation, but also to water amorphization and climate change modeling.

  • ice water Interfacial Free Energy for the tip4p tip4p 2005 tip4p ice and mw models as obtained from the mold integration technique
    Journal of Physical Chemistry C, 2016
    Co-Authors: Jorge R Espinosa, Carlos Vega, Eduardo Sanz
    Abstract:

    The Freezing of water is greatly influenced by the ice–water Interfacial Free Energy. Yet, no consistent experimental measures of this thermodynamic parameter can be found. In this work we provide estimates for the ice Ih–water Interfacial Free Energy at the normal melting temperature for different crystal planes (basal, primary prismatic, and secondary prismatic) using some widely used water models: TIP4P, TIP4P/2005, TIP4P/Ice, and mW. To compute the Interfacial Free Energy, we use the mold integration method. It consists in calculating the work needed to induce the formation of a crystal slab in the fluid at coexistence conditions with the aid of a mold of potential Energy wells whose structure is that of the crystal plane under study. The basal plane has the lowest Interfacial Free Energy in all models of the TIP4P family. For the mW model we could not resolve differences in Interfacial Free Energy between different orientations. The Interfacial Free energies averaged over all crystal orientations we ...

  • Ice–Water Interfacial Free Energy for the TIP4P, TIP4P/2005, TIP4P/Ice, and mW Models As Obtained from the Mold Integration Technique
    The Journal of Physical Chemistry C, 2016
    Co-Authors: Jorge R Espinosa, Carlos Vega, Eduardo Sanz
    Abstract:

    The Freezing of water is greatly influenced by the ice–water Interfacial Free Energy. Yet, no consistent experimental measures of this thermodynamic parameter can be found. In this work we provide estimates for the ice Ih–water Interfacial Free Energy at the normal melting temperature for different crystal planes (basal, primary prismatic, and secondary prismatic) using some widely used water models: TIP4P, TIP4P/2005, TIP4P/Ice, and mW. To compute the Interfacial Free Energy, we use the mold integration method. It consists in calculating the work needed to induce the formation of a crystal slab in the fluid at coexistence conditions with the aid of a mold of potential Energy wells whose structure is that of the crystal plane under study. The basal plane has the lowest Interfacial Free Energy in all models of the TIP4P family. For the mW model we could not resolve differences in Interfacial Free Energy between different orientations. The Interfacial Free energies averaged over all crystal orientations we ...

  • the crystal fluid Interfacial Free Energy and nucleation rate of nacl from different simulation methods
    Journal of Chemical Physics, 2015
    Co-Authors: Jorge R Espinosa, Carlos Vega, Chantal Valeriani, Eduardo Sanz
    Abstract:

    In this work, we calculate the crystal-fluid Interfacial Free Energy, γcf, for the Tosi-Fumi model of NaCl using three different simulation techniques: seeding, umbrella sampling, and mold integration. The three techniques give an orientationaly averaged γcf of about 100 mJ/m2. Moreover, we observe that the shape of crystalline clusters embedded in the supercooled fluid is spherical. Using the mold integration technique, we compute γcf for four different crystal orientations. The obtained Interfacial Free energies range from 100 to 114 mJ/m2, being (100) and (111) the crystal planes with the lowest and highest γcf, respectively. Within the accuracy of our calculations, the Interfacial Free Energy either does not depend on temperature or changes very smoothly with it. Combining the seeding technique with classical nucleation theory, we also estimate nucleation Free Energy barriers and nucleation rates for a wide temperature range (800-1040 K). The obtained results compare quite well with brute force calcul...

Jorge R Espinosa - One of the best experts on this subject based on the ideXlab platform.

  • Interfacial Free Energy and tolman length of curved liquid solid interfaces from equilibrium studies
    The Journal of Physical Chemistry, 2020
    Co-Authors: Pablo Montero De Hijes, Jorge R Espinosa, Valentino Bianco, Eduardo Sanz Garcia, Carlos Vega De Las Heras
    Abstract:

    In this work, we study by means of simulations of hard spheres the equilibrium between a spherical solid cluster and the fluid. In the NVT ensemble we observe stable/metastable clusters of the solid phase in equilibrium with the fluid, representing configurations that are global/local minima of the Helmholtz Free Energy. Then, we run NpT simulations of the equilibrated system at the average pressure of the NVT run and observe that the clusters are critical because they grow/shrink with a probability of 1/2. Therefore, a crystal cluster equilibrated in the NVT ensemble corresponds to a Gibbs Free Energy maximum where the nucleus is in unstable equilibrium with the surrounding fluid, in accordance with what has been recently shown for vapor bubbles in equilibrium with the liquid. Then, within the Seeding framework, we use Classical Nucleation Theory to obtain both the Interfacial Free Energy γ and the nucleation rate. The latter is in very good agreement with independent estimates using techniques that do not rely on Classical Nucleation Theory when the mislabeling criterion is used to identify the molecules of the solid cluster. We therefore argue that the radius obtained from the mislabeling criterion provides a good approximation for the radius of tension, R_s . We obtain an estimate of the Tolman length by extrapolating the difference between R e (the Gibbs dividing surface) and R s to infinite radius. We show that such definition of the Tolman length coincides with that obtained by fitting γ versus 1/R_s to a straight line as recently applied to hard spheres.

  • Interfacial Free Energy of a liquid solid interface its change with curvature
    Journal of Chemical Physics, 2019
    Co-Authors: Montero P De Hijes, Jorge R Espinosa, Eduardo Sanz, Carlos Vega
    Abstract:

    We analyze the changes in the Interfacial Free Energy between a spherical solid cluster and a fluid due to the change of the radius of the solid. Interfacial Free energies from nucleation studies using the seeding technique for four different systems, being hard spheres, Lennard-Jones, and two models of water (mW and TIP4P/ICE), were plotted as a function of the inverse of the radius of the solid cluster. In all cases, the Interfacial Free Energy was a linear function of the inverse of the radius of the solid cluster and this is consistent with Tolman’s equation. This linear behavior is shown not only in isotherms but also along isobars. The effect of curvature on the Interfacial Free Energy is more pronounced in water, followed by hard spheres, and smaller for Lennard-Jones particles. We show that it is possible to estimate nucleation rates of Lennard-Jones particles at different pressures by using information from simple NpT simulations and taking into account the variation of the Interfacial Free Energy with the radius of the solid cluster. Neglecting the effects of the radius on the Interfacial Free Energy (capillarity approximation) leads to incorrect values of the nucleation rate. For the Lennard-Jones system, the homogeneous nucleation curve is not parallel to the melting curve as was found for water in previous work. This is due to the increase in the Interfacial Free Energy along the coexistence curve as the pressure increases. This work presents a simple and relatively straightforward way to approximately estimate nucleation rates.We analyze the changes in the Interfacial Free Energy between a spherical solid cluster and a fluid due to the change of the radius of the solid. Interfacial Free energies from nucleation studies using the seeding technique for four different systems, being hard spheres, Lennard-Jones, and two models of water (mW and TIP4P/ICE), were plotted as a function of the inverse of the radius of the solid cluster. In all cases, the Interfacial Free Energy was a linear function of the inverse of the radius of the solid cluster and this is consistent with Tolman’s equation. This linear behavior is shown not only in isotherms but also along isobars. The effect of curvature on the Interfacial Free Energy is more pronounced in water, followed by hard spheres, and smaller for Lennard-Jones particles. We show that it is possible to estimate nucleation rates of Lennard-Jones particles at different pressures by using information from simple NpT simulations and taking into account the variation of the Interfacial Free energ...

  • Interfacial Free Energy as the key to the pressure induced deceleration of ice nucleation
    Physical Review Letters, 2016
    Co-Authors: Jorge R Espinosa, Carlos Vega, Chantal Valeriani, Alberto Zaragoza, P Rosalespelaez, Caridad Navarro, Eduardo Sanz
    Abstract:

    : The avoidance of water Freezing is the holy grail in the cryopreservation of biological samples, food, and organs. Fast cooling rates are used to beat ice nucleation and avoid cell damage. This strategy can be enhanced by applying high pressures to decrease the nucleation rate, but the physics behind this procedure has not been fully understood yet. We perform computer experiments to investigate ice nucleation at high pressures consisting in embedding ice seeds in supercooled water. We find that the slowing down of the nucleation rate is mainly due to an increase of the ice I-water Interfacial Free Energy with pressure. Our work also clarifies the molecular mechanism of ice nucleation for a wide pressure range. This study is not only relevant to cryopreservation, but also to water amorphization and climate change modeling.

  • ice water Interfacial Free Energy for the tip4p tip4p 2005 tip4p ice and mw models as obtained from the mold integration technique
    Journal of Physical Chemistry C, 2016
    Co-Authors: Jorge R Espinosa, Carlos Vega, Eduardo Sanz
    Abstract:

    The Freezing of water is greatly influenced by the ice–water Interfacial Free Energy. Yet, no consistent experimental measures of this thermodynamic parameter can be found. In this work we provide estimates for the ice Ih–water Interfacial Free Energy at the normal melting temperature for different crystal planes (basal, primary prismatic, and secondary prismatic) using some widely used water models: TIP4P, TIP4P/2005, TIP4P/Ice, and mW. To compute the Interfacial Free Energy, we use the mold integration method. It consists in calculating the work needed to induce the formation of a crystal slab in the fluid at coexistence conditions with the aid of a mold of potential Energy wells whose structure is that of the crystal plane under study. The basal plane has the lowest Interfacial Free Energy in all models of the TIP4P family. For the mW model we could not resolve differences in Interfacial Free Energy between different orientations. The Interfacial Free energies averaged over all crystal orientations we ...

  • Ice–Water Interfacial Free Energy for the TIP4P, TIP4P/2005, TIP4P/Ice, and mW Models As Obtained from the Mold Integration Technique
    The Journal of Physical Chemistry C, 2016
    Co-Authors: Jorge R Espinosa, Carlos Vega, Eduardo Sanz
    Abstract:

    The Freezing of water is greatly influenced by the ice–water Interfacial Free Energy. Yet, no consistent experimental measures of this thermodynamic parameter can be found. In this work we provide estimates for the ice Ih–water Interfacial Free Energy at the normal melting temperature for different crystal planes (basal, primary prismatic, and secondary prismatic) using some widely used water models: TIP4P, TIP4P/2005, TIP4P/Ice, and mW. To compute the Interfacial Free Energy, we use the mold integration method. It consists in calculating the work needed to induce the formation of a crystal slab in the fluid at coexistence conditions with the aid of a mold of potential Energy wells whose structure is that of the crystal plane under study. The basal plane has the lowest Interfacial Free Energy in all models of the TIP4P family. For the mW model we could not resolve differences in Interfacial Free Energy between different orientations. The Interfacial Free energies averaged over all crystal orientations we ...

Dong-hee Kang - One of the best experts on this subject based on the ideXlab platform.

  • Interfacial Free Energy controlling glass-forming ability of Cu-Zr alloys.
    Scientific reports, 2014
    Co-Authors: Dong-hee Kang, Hao Zhang, Hanbyeol Yoo, Hyun Hwi Lee, Sooheyong Lee, Geun Woo Lee, Hongbo Lou, Xiaodong Wang, Qingping Cao, D.x. Zhang
    Abstract:

    Glass is a Freezing phase of a deeply supercooled liquid. Despite its simple definition, the origin of glass forming ability (GFA) is still ambiguous, even for binary Cu-Zr alloys. Here, we directly study the stability of the supercooled Cu-Zr liquids where we find that Cu64Zr36 at a supercooled temperature shows deeper undercoolability and longer persistence than other neighbouring compositions with an equivalent driving Gibbs Free Energy. This observation implies that the GFA of the Cu-Zr alloys is significantly affected by crystal-liquid Interfacial Free Energy. In particular, the crystal-liquid Interfacial Free Energy of Cu64Zr36 in our measurement was higher than that of other neighbouring liquids and, coincidently a molecular dynamics simulation reveals a larger glass-glass Interfacial Energy value at this composition, which reflects more distinct configuration difference between liquid and crystal phase. The present results demonstrate that the higher crystal-liquid Interfacial Free Energy is a prerequisite of good GFA of the Cu-Zr alloys.

  • Nanosized Nucleus-Supercooled Liquid Interfacial Free Energy and Thermophysical Properties of Early and Late Transition Liquid Metals
    Crystal Growth & Design, 2014
    Co-Authors: Dong-hee Kang, Hanbyeol Yoo, Sangho Jeon, Takehiko Ishikawa, Junpei T. Okada, Paul-françois Paradis, Geun Woo Lee
    Abstract:

    Crystal–liquid Interfacial Free Energy is important to understand in crystal study, for example, nucleation, crystal growth, and vitrification. Here, we report the nanosized nucleus-supercooled liquid Interfacial Free Energy of early and late transition liquid metals using the electrostatic levitation (ESL) technique and classical homogeneous nucleation theory (CNT). For the estimation of the Interfacial Free Energy, we obtained thermophysical parameters of the transition liquid metals (Ti, Fe, Ni, Zr, Nb, Rh, and Hf), such as hypercooling limit (ΔThyp), specific heat (Cp), total hemispherical emissivity (eT), and density (ρ). The estimated Interfacial Free energies of Ti, Ni, and Zr agreed well with a previous report having similar hypercooling limit and fusion enthalpy, while Fe, Nb, Rh, and Hf show different values from the report. This reflects the importance of accurate measurement of the two quantities. The obtained Turnbull’s coefficients (α) of the liquid metals is higher than 0.45. The interfacia...

  • crystal liquid Interfacial Free Energy and thermophysical properties of pure liquid ti using electrostatic levitation hypercooling limit specific heat total hemispherical emissivity density and Interfacial Free Energy
    The Journal of Chemical Thermodynamics, 2013
    Co-Authors: Geun Woo Lee, Sangho Jeon, Cheolmin Park, Dong-hee Kang
    Abstract:

    Abstract Thermophysical properties of liquid Ti are measured by a newly developed electrostatic levitation. In this study, we measure a hypercooling limit (ΔThyp), specific heat (Cp), total hemispherical emissivity (eT), and density (ρ) of liquid Ti. The ΔThyp of the liquid Ti is 341 K. The Cp of the liquid Ti shows very weak temperature dependence during supercooling. The eT and ρ of the liquid Ti are given by 0.329 and ρ(T) (g/cm3) = (4.16 − 2.36) · 10−4 (T − Tm). Finally, the Interfacial Free Energy is estimated with the measured thermophysical parameters. The Interfacial Free Energy is 0.164 J/m2, and Turnbull’s coefficient is 0.48.

  • Crystal–Liquid Interfacial Free Energy of Supercooled Liquid Fe Using a Containerless Technique
    Crystal Growth & Design, 2013
    Co-Authors: Geun Woo Lee, Shangho Jeon, Dong-hee Kang
    Abstract:

    We report a crystal–liquid Interfacial Free Energy of a supercooled liquid Fe, which is estimated from the classical homogeneous nucleation theory, using a containerless technique, electrostatic le...

  • crystal liquid Interfacial Free Energy of supercooled liquid fe using a containerless technique
    Crystal Growth & Design, 2013
    Co-Authors: Geun Woo Lee, Shangho Jeon, Dong-hee Kang
    Abstract:

    We report a crystal–liquid Interfacial Free Energy of a supercooled liquid Fe, which is estimated from the classical homogeneous nucleation theory, using a containerless technique, electrostatic le...

Carlos Vega - One of the best experts on this subject based on the ideXlab platform.

  • Interfacial Free Energy of a liquid solid interface its change with curvature
    Journal of Chemical Physics, 2019
    Co-Authors: Montero P De Hijes, Jorge R Espinosa, Eduardo Sanz, Carlos Vega
    Abstract:

    We analyze the changes in the Interfacial Free Energy between a spherical solid cluster and a fluid due to the change of the radius of the solid. Interfacial Free energies from nucleation studies using the seeding technique for four different systems, being hard spheres, Lennard-Jones, and two models of water (mW and TIP4P/ICE), were plotted as a function of the inverse of the radius of the solid cluster. In all cases, the Interfacial Free Energy was a linear function of the inverse of the radius of the solid cluster and this is consistent with Tolman’s equation. This linear behavior is shown not only in isotherms but also along isobars. The effect of curvature on the Interfacial Free Energy is more pronounced in water, followed by hard spheres, and smaller for Lennard-Jones particles. We show that it is possible to estimate nucleation rates of Lennard-Jones particles at different pressures by using information from simple NpT simulations and taking into account the variation of the Interfacial Free Energy with the radius of the solid cluster. Neglecting the effects of the radius on the Interfacial Free Energy (capillarity approximation) leads to incorrect values of the nucleation rate. For the Lennard-Jones system, the homogeneous nucleation curve is not parallel to the melting curve as was found for water in previous work. This is due to the increase in the Interfacial Free Energy along the coexistence curve as the pressure increases. This work presents a simple and relatively straightforward way to approximately estimate nucleation rates.We analyze the changes in the Interfacial Free Energy between a spherical solid cluster and a fluid due to the change of the radius of the solid. Interfacial Free energies from nucleation studies using the seeding technique for four different systems, being hard spheres, Lennard-Jones, and two models of water (mW and TIP4P/ICE), were plotted as a function of the inverse of the radius of the solid cluster. In all cases, the Interfacial Free Energy was a linear function of the inverse of the radius of the solid cluster and this is consistent with Tolman’s equation. This linear behavior is shown not only in isotherms but also along isobars. The effect of curvature on the Interfacial Free Energy is more pronounced in water, followed by hard spheres, and smaller for Lennard-Jones particles. We show that it is possible to estimate nucleation rates of Lennard-Jones particles at different pressures by using information from simple NpT simulations and taking into account the variation of the Interfacial Free energ...

  • Interfacial Free Energy as the key to the pressure induced deceleration of ice nucleation
    Physical Review Letters, 2016
    Co-Authors: Jorge R Espinosa, Carlos Vega, Chantal Valeriani, Alberto Zaragoza, P Rosalespelaez, Caridad Navarro, Eduardo Sanz
    Abstract:

    : The avoidance of water Freezing is the holy grail in the cryopreservation of biological samples, food, and organs. Fast cooling rates are used to beat ice nucleation and avoid cell damage. This strategy can be enhanced by applying high pressures to decrease the nucleation rate, but the physics behind this procedure has not been fully understood yet. We perform computer experiments to investigate ice nucleation at high pressures consisting in embedding ice seeds in supercooled water. We find that the slowing down of the nucleation rate is mainly due to an increase of the ice I-water Interfacial Free Energy with pressure. Our work also clarifies the molecular mechanism of ice nucleation for a wide pressure range. This study is not only relevant to cryopreservation, but also to water amorphization and climate change modeling.

  • ice water Interfacial Free Energy for the tip4p tip4p 2005 tip4p ice and mw models as obtained from the mold integration technique
    Journal of Physical Chemistry C, 2016
    Co-Authors: Jorge R Espinosa, Carlos Vega, Eduardo Sanz
    Abstract:

    The Freezing of water is greatly influenced by the ice–water Interfacial Free Energy. Yet, no consistent experimental measures of this thermodynamic parameter can be found. In this work we provide estimates for the ice Ih–water Interfacial Free Energy at the normal melting temperature for different crystal planes (basal, primary prismatic, and secondary prismatic) using some widely used water models: TIP4P, TIP4P/2005, TIP4P/Ice, and mW. To compute the Interfacial Free Energy, we use the mold integration method. It consists in calculating the work needed to induce the formation of a crystal slab in the fluid at coexistence conditions with the aid of a mold of potential Energy wells whose structure is that of the crystal plane under study. The basal plane has the lowest Interfacial Free Energy in all models of the TIP4P family. For the mW model we could not resolve differences in Interfacial Free Energy between different orientations. The Interfacial Free energies averaged over all crystal orientations we ...

  • Ice–Water Interfacial Free Energy for the TIP4P, TIP4P/2005, TIP4P/Ice, and mW Models As Obtained from the Mold Integration Technique
    The Journal of Physical Chemistry C, 2016
    Co-Authors: Jorge R Espinosa, Carlos Vega, Eduardo Sanz
    Abstract:

    The Freezing of water is greatly influenced by the ice–water Interfacial Free Energy. Yet, no consistent experimental measures of this thermodynamic parameter can be found. In this work we provide estimates for the ice Ih–water Interfacial Free Energy at the normal melting temperature for different crystal planes (basal, primary prismatic, and secondary prismatic) using some widely used water models: TIP4P, TIP4P/2005, TIP4P/Ice, and mW. To compute the Interfacial Free Energy, we use the mold integration method. It consists in calculating the work needed to induce the formation of a crystal slab in the fluid at coexistence conditions with the aid of a mold of potential Energy wells whose structure is that of the crystal plane under study. The basal plane has the lowest Interfacial Free Energy in all models of the TIP4P family. For the mW model we could not resolve differences in Interfacial Free Energy between different orientations. The Interfacial Free energies averaged over all crystal orientations we ...

  • the crystal fluid Interfacial Free Energy and nucleation rate of nacl from different simulation methods
    Journal of Chemical Physics, 2015
    Co-Authors: Jorge R Espinosa, Carlos Vega, Chantal Valeriani, Eduardo Sanz
    Abstract:

    In this work, we calculate the crystal-fluid Interfacial Free Energy, γcf, for the Tosi-Fumi model of NaCl using three different simulation techniques: seeding, umbrella sampling, and mold integration. The three techniques give an orientationaly averaged γcf of about 100 mJ/m2. Moreover, we observe that the shape of crystalline clusters embedded in the supercooled fluid is spherical. Using the mold integration technique, we compute γcf for four different crystal orientations. The obtained Interfacial Free energies range from 100 to 114 mJ/m2, being (100) and (111) the crystal planes with the lowest and highest γcf, respectively. Within the accuracy of our calculations, the Interfacial Free Energy either does not depend on temperature or changes very smoothly with it. Combining the seeding technique with classical nucleation theory, we also estimate nucleation Free Energy barriers and nucleation rates for a wide temperature range (800-1040 K). The obtained results compare quite well with brute force calcul...

Geun Woo Lee - One of the best experts on this subject based on the ideXlab platform.

  • Formation of Metastable Crystals from Supercooled, Supersaturated, and Supercompressed Liquids: Role of Crystal-Liquid Interfacial Free Energy
    Crystals, 2017
    Co-Authors: Geun Woo Lee
    Abstract:

    The formation mechanism of metastable crystals from metastable liquids still remains elusive, although controlling the metastability of crystals and liquids already plays a crucial role in designing new materials in physics, chemistry, biology, and materials science. This review article describes how metastable phases can be obtained by controlling temperature, concentration, and pressure. In particular, I show the role of crystal-liquid Interfacial Free Energy in the formation of metastable crystals from metastable liquids at a given driving force. In a microscopic viewpoint, local structure similarity between the metastable crystals and liquid determines the crystal-liquid Interfacial Free Energy, and thus the nucleation barrier for the metastable crystals. The effect of the Interfacial Free Energy on the formation of metastable crystals from supercooled, supersaturated, and supercompressed liquids will be demonstrated with metallic liquids, aqueous solutions, and water.

  • Interfacial Free Energy controlling glass-forming ability of Cu-Zr alloys.
    Scientific reports, 2014
    Co-Authors: Dong-hee Kang, Hao Zhang, Hanbyeol Yoo, Hyun Hwi Lee, Sooheyong Lee, Geun Woo Lee, Hongbo Lou, Xiaodong Wang, Qingping Cao, D.x. Zhang
    Abstract:

    Glass is a Freezing phase of a deeply supercooled liquid. Despite its simple definition, the origin of glass forming ability (GFA) is still ambiguous, even for binary Cu-Zr alloys. Here, we directly study the stability of the supercooled Cu-Zr liquids where we find that Cu64Zr36 at a supercooled temperature shows deeper undercoolability and longer persistence than other neighbouring compositions with an equivalent driving Gibbs Free Energy. This observation implies that the GFA of the Cu-Zr alloys is significantly affected by crystal-liquid Interfacial Free Energy. In particular, the crystal-liquid Interfacial Free Energy of Cu64Zr36 in our measurement was higher than that of other neighbouring liquids and, coincidently a molecular dynamics simulation reveals a larger glass-glass Interfacial Energy value at this composition, which reflects more distinct configuration difference between liquid and crystal phase. The present results demonstrate that the higher crystal-liquid Interfacial Free Energy is a prerequisite of good GFA of the Cu-Zr alloys.

  • Nanosized Nucleus-Supercooled Liquid Interfacial Free Energy and Thermophysical Properties of Early and Late Transition Liquid Metals
    Crystal Growth & Design, 2014
    Co-Authors: Dong-hee Kang, Hanbyeol Yoo, Sangho Jeon, Takehiko Ishikawa, Junpei T. Okada, Paul-françois Paradis, Geun Woo Lee
    Abstract:

    Crystal–liquid Interfacial Free Energy is important to understand in crystal study, for example, nucleation, crystal growth, and vitrification. Here, we report the nanosized nucleus-supercooled liquid Interfacial Free Energy of early and late transition liquid metals using the electrostatic levitation (ESL) technique and classical homogeneous nucleation theory (CNT). For the estimation of the Interfacial Free Energy, we obtained thermophysical parameters of the transition liquid metals (Ti, Fe, Ni, Zr, Nb, Rh, and Hf), such as hypercooling limit (ΔThyp), specific heat (Cp), total hemispherical emissivity (eT), and density (ρ). The estimated Interfacial Free energies of Ti, Ni, and Zr agreed well with a previous report having similar hypercooling limit and fusion enthalpy, while Fe, Nb, Rh, and Hf show different values from the report. This reflects the importance of accurate measurement of the two quantities. The obtained Turnbull’s coefficients (α) of the liquid metals is higher than 0.45. The interfacia...

  • crystal liquid Interfacial Free Energy and thermophysical properties of pure liquid ti using electrostatic levitation hypercooling limit specific heat total hemispherical emissivity density and Interfacial Free Energy
    The Journal of Chemical Thermodynamics, 2013
    Co-Authors: Geun Woo Lee, Sangho Jeon, Cheolmin Park, Dong-hee Kang
    Abstract:

    Abstract Thermophysical properties of liquid Ti are measured by a newly developed electrostatic levitation. In this study, we measure a hypercooling limit (ΔThyp), specific heat (Cp), total hemispherical emissivity (eT), and density (ρ) of liquid Ti. The ΔThyp of the liquid Ti is 341 K. The Cp of the liquid Ti shows very weak temperature dependence during supercooling. The eT and ρ of the liquid Ti are given by 0.329 and ρ(T) (g/cm3) = (4.16 − 2.36) · 10−4 (T − Tm). Finally, the Interfacial Free Energy is estimated with the measured thermophysical parameters. The Interfacial Free Energy is 0.164 J/m2, and Turnbull’s coefficient is 0.48.

  • Crystal–Liquid Interfacial Free Energy of Supercooled Liquid Fe Using a Containerless Technique
    Crystal Growth & Design, 2013
    Co-Authors: Geun Woo Lee, Shangho Jeon, Dong-hee Kang
    Abstract:

    We report a crystal–liquid Interfacial Free Energy of a supercooled liquid Fe, which is estimated from the classical homogeneous nucleation theory, using a containerless technique, electrostatic le...