The Experts below are selected from a list of 19818 Experts worldwide ranked by ideXlab platform
Van P Carey - One of the best experts on this subject based on the ideXlab platform.
-
hybrid modeling of Interfacial Region thermophysics and intrinsic stability of thin free liquid films
2010Co-Authors: Yu Gan, Van P CareyAbstract:Abstract The film rupture process that dictates merging of adjacent bubbles is particularly important in nucleate boiling heat transfer, bubbly two-phase flow in small tubes, and the mechanisms that dictate the Leidenfrost transition. To understand the mechanisms of bubble merging in nanostructured boiling surfaces and in nanotubes, it is useful to explore film stability and onset of rupture at the molecular level. This paper reports the results of such an investigation using a hybrid analysis scheme that combines a new formulation of capillarity theory for free liquid films with molecular dynamics (MD) simulations that use similar interaction potentials. Two forms of our molecular film capillarity theory are developed here: one for non-polar fluids based on a Lennard-Jones interaction potential, and a second specifically for water using a modified treatment of the SPC/E interaction potential that accounts for water dipole interactions. The hybrid model has the advantage that the capillarity theory provides theoretical relationships among parameters that govern film structure and thermophysical behavior, while the companion MD simulations allow more detailed molecular level exploration of the film thermophysics. Results obtained with the hybrid model indicate that wave instability predominates as an onset of rupture mechanism for liquid films of macroscopic extent, but for free liquid films with nanoscale lateral extent (in, for example, nanostructured boiling surfaces), lack of core stability is more likely to be the mechanism. The implications of these predictions for film rupture and bubble merging in nanostructured surfaces and nanotubes are examined in detail.
-
liquid vapor phase change phenomena an introduction to the thermophysics of vaporization and condensation processes in heat transfer equipment
2008Co-Authors: Van P CareyAbstract:Pt. 1. Thermodynamic and mechanical aspects of Interfacial phenomena and phase transitions -- 1. Liquid-vapor Interfacial Region - A nanoscale perspective -- 1.1. Molecular perspective on liquid-vapor transitions -- 1.2. Interfacial Region - Molecular theories of capillarity -- 1.3. Nanoscale features of the Interfacial Region -- 1.4. Molecular dynamics simulation studies of Interfacial Region thermophysics -- 2. Liquid-vapor interface - a macroscopic treatment -- 2.1. Thermodynamic analysis of Interfacial tension effects -- 2.2. Determination of interface shapes at equilibrium -- 2.3. Temperature and surfactant effects on Interfacial tension -- 2.4. Surface tension in mixtures -- 2.5. Near critical point behavior -- 2.6. Effects of Interfacial tension gradients -- 3. Wetting phenomena and contact angles -- 3.1. Equilibrium contact angles on smooth surfaces -- 3.2. Wettability, cohesion, and adhesion -- 3.3. Effect of liquid surface tension on contact angle -- 3.4. Adsorption --^
-
molecular dynamics exploration of thin liquid films on solid surfaces 1 monatomic fluid films
2005Co-Authors: Aaron P Wemhoff, Van P CareyAbstract:The thickness of the Interfacial Region dividing bulk liquid and vapor Regions is typically on the order of a few molecular diameters. Furthermore, in systems where the characteristic length scale is the same order of magnitude as the thickness of the interface such as a thin liquid film on a solid surface, behavior may be different than that for larger systems. The small thickness of such films leads to difficult experimental observation of phenomena within various Regions of the film: the wall-affected Region, the bulk liquid, and the liquid–vapor Interfacial Region. A hybrid simulation methodology is applied that combines a deterministic molecular dynamics simulation of the liquid Regions with a stochastic treatment of the far-field vapor Region boundary. In this simulation scheme, the imposed far-field pressure may be held fixed or iterated as the simulation is advanced in time until the mass in the system stabilizes at the specified temperature, which establishes the equilibrium saturation vapor pres...
-
thermodynamic properties and structure of the liquid vapor interface a neoclassical redlich kwong model
2003Co-Authors: Van P CareyAbstract:It is well known that the classical mean field theory of van der Waals for liquid–vapor Interfacial Region properties deviates from real fluid behavior in several important ways. In particular, the variations of the surface tension and Interfacial Region thickness with temperature near the critical point are not consistent with those for real fluids. This paper presents a modified version of the classical mean field model that incorporates Redlich–Kwong fluid properties. It is shown here that this neoclassical Redlich–Kwong fluid model predicts property variations with temperature that agree better with measured data for real fluids. Predictions of the critical exponents associated with the temperature variation of surface tension and Interfacial Region thickness are developed from the Redlich–Kwong model. This new model predicts that surface tension varies about proportional to (1−T/Tc)1.33 and that the Interfacial Region thickness varies about proportional to (1−T/Tc)−0.67, with T and Tc being the syste...
-
molecular dynamics exploration of properties in the liquid vapor Interfacial Region
2003Co-Authors: Aaron P Wemhoff, Van P CareyAbstract:Molecular dynamics (MD) simulations of liquid-vapor interfaces were performed to determine mean property variations and property fluctuations in the liquid-vapor Interfacial Region at various reduced temperatures. The Interfacial Region typically has a thickness on the order of a few nanometers for systems of practical interest. The system’s initial conditions were specified as a bulk liquid Region sandwiched between two bulk vapor Regions. Simulations were run using a Lennard-Jones 6-12 potential function between the atoms with appropriate parameters for Argon atoms. As the simulation was performed, Interfacial Region property data was collected over time. The resulting property data are shown to establish trends similar to those indicated by theoretical and experimental results reported elsewhere. The peak fluctuations of mass density and free energy density were determined to be approximately equal in magnitude when normalized with the difference in their respective bulk values at a given temperature. These fluctuations were found to increase rapidly with temperature. The fluctuations in the Interfacial thickness and Interfacial position follow a functional dependence on temperature similar to that exhibited by the mean value of Interfacial thickness. In addition to exploring fluctuations in the Interfacial Region, two new methods were developed to determine Interfacial tension through methods involving integration of excess free energy density across the Interfacial Region. These techniques were shown to yield mean results similar to theoretical predictions and those using conventional techniques. In addition, the time required for computation using the new techniques is significantly reduced due to less computational time per step and fewer required steps for convergence to a mean value.Copyright © 2003 by ASME
Jack F Douglas - One of the best experts on this subject based on the ideXlab platform.
-
string like collective motion and diffusion in the Interfacial Region of ice
2017Co-Authors: Xinyi Wang, Hao Zhang, Xuhang Tong, Jack F DouglasAbstract:We investigate collective molecular motion and the self-diffusion coefficient Ds of water molecules in the mobile Interfacial layer of the secondary prismatic plane (112¯0) of hexagonal ice by molecular dynamics simulation based on the TIP4P/2005 water potential and a metrology of collective motion drawn from the field of glass-forming liquids. The width ξ of the mobile Interfacial layer varies from a monolayer to a few nm as the temperature is increased towards the melting temperature Tm, in accordance with recent simulations and many experimental studies, although different experimental methods have differed in their precise estimates of the thickness of this layer. We also find that the dynamics within this mobile Interfacial ice layer is “dynamically heterogeneous” in a fashion that has many features in common with glass-forming liquids and the Interfacial dynamics of crystalline Ni over the same reduced temperature range, 2/3 < T/Tm < 1. In addition to exhibiting non-Gaussian diffusive transport, decoupling between mass diffusion and the structural relaxation time, and stretched exponential relaxation, we find string-like collective molecular exchange motion in the Interfacial zone within the ice Interfacial layer and colored noise fluctuations in the mean square molecular atomic displacement 〈u2〉 after a “caging time” of 1 ps, i.e., the Debye-Waller factor. However, while the heterogeneous dynamics of ice is clearly similar in many ways to molecular and colloidal glass-forming materials, we find distinct trends between the diffusion coefficient activation energy Ea for diffusion Ds and the Interfacial width ξ from the scale of collective string-like motion L than those found in glass-forming liquids.We investigate collective molecular motion and the self-diffusion coefficient Ds of water molecules in the mobile Interfacial layer of the secondary prismatic plane (112¯0) of hexagonal ice by molecular dynamics simulation based on the TIP4P/2005 water potential and a metrology of collective motion drawn from the field of glass-forming liquids. The width ξ of the mobile Interfacial layer varies from a monolayer to a few nm as the temperature is increased towards the melting temperature Tm, in accordance with recent simulations and many experimental studies, although different experimental methods have differed in their precise estimates of the thickness of this layer. We also find that the dynamics within this mobile Interfacial ice layer is “dynamically heterogeneous” in a fashion that has many features in common with glass-forming liquids and the Interfacial dynamics of crystalline Ni over the same reduced temperature range, 2/3 < T/Tm < 1. In addition to exhibiting non-Gaussian diffusive transport, dec...
-
string like collective motion and diffusion in the Interfacial Region of ice
2017Co-Authors: Xinyi Wang, Hao Zhang, Xuhang Tong, Jack F DouglasAbstract:We investigate collective molecular motion and the self-diffusion coefficient Ds of water molecules in the mobile Interfacial layer of the secondary prismatic plane (112¯0) of hexagonal ice by molecular dynamics simulation based on the TIP4P/2005 water potential and a metrology of collective motion drawn from the field of glass-forming liquids. The width ξ of the mobile Interfacial layer varies from a monolayer to a few nm as the temperature is increased towards the melting temperature Tm, in accordance with recent simulations and many experimental studies, although different experimental methods have differed in their precise estimates of the thickness of this layer. We also find that the dynamics within this mobile Interfacial ice layer is “dynamically heterogeneous” in a fashion that has many features in common with glass-forming liquids and the Interfacial dynamics of crystalline Ni over the same reduced temperature range, 2/3 < T/Tm < 1. In addition to exhibiting non-Gaussian diffusive transport, decoupling between mass diffusion and the structural relaxation time, and stretched exponential relaxation, we find string-like collective molecular exchange motion in the Interfacial zone within the ice Interfacial layer and colored noise fluctuations in the mean square molecular atomic displacement 〈u2〉 after a “caging time” of 1 ps, i.e., the Debye-Waller factor. However, while the heterogeneous dynamics of ice is clearly similar in many ways to molecular and colloidal glass-forming materials, we find distinct trends between the diffusion coefficient activation energy Ea for diffusion Ds and the Interfacial width ξ from the scale of collective string-like motion L than those found in glass-forming liquids.
-
influence of string like cooperative atomic motion on surface diffusion in the 110 Interfacial Region of crystalline ni
2015Co-Authors: Hao Zhang, Ying Yang, Jack F DouglasAbstract:Although we often think about crystalline materials in terms of highly organized arrays of atoms, molecules, or even colloidal particles, many of the important properties of this diverse class of materials relating to their catalytic behavior, thermodynamic stability, and mechanical properties derive from the dynamics and thermodynamics of their Interfacial Regions, which we find they have a dynamics more like glass-forming (GF) liquids than crystals at elevated temperatures. This is a general problem arising in any attempt to model the properties of naturally occurring crystalline materials since many aspects of the dynamics of glass-forming liquids remain mysterious. We examine the nature of this phenomenon in the “simple” case of the (110) interface of crystalline Ni, based on a standard embedded-atom model potential, and we then quantify the collective dynamics in this Interfacial Region using newly developed methods for characterizing the cooperative dynamics of glass-forming liquids. As in our forme...
-
influence of string like cooperative atomic motion on surface diffusion in the 110 Interfacial Region of crystalline ni
2015Co-Authors: Hao Zhang, Ying Yang, Jack F DouglasAbstract:Although we often think about crystalline materials in terms of highly organized arrays of atoms, molecules, or even colloidal particles, many of the important properties of this diverse class of materials relating to their catalytic behavior, thermodynamic stability, and mechanical properties derive from the dynamics and thermodynamics of their Interfacial Regions, which we find they have a dynamics more like glass-forming (GF) liquids than crystals at elevated temperatures. This is a general problem arising in any attempt to model the properties of naturally occurring crystalline materials since many aspects of the dynamics of glass-forming liquids remain mysterious. We examine the nature of this phenomenon in the “simple” case of the (110) interface of crystalline Ni, based on a standard embedded-atom model potential, and we then quantify the collective dynamics in this Interfacial Region using newly developed methods for characterizing the cooperative dynamics of glass-forming liquids. As in our former studies of the Interfacial dynamics of grain-boundaries and the Interfacial dynamics of crystalline Ni nanoparticles (NPs), we find that the interface of bulk crystalline Ni exhibits all the characteristics of glass-forming materials, even at temperatures well below the equilibrium crystal melting temperature, Tm. This perspective offers a new approach to modeling and engineering the properties of crystalline materials.
Marcin Majda - One of the best experts on this subject based on the ideXlab platform.
-
electrochemistry of tempo an assessment of the water diffusion constant in the aqueous liquid vapor Interfacial Region
2013Co-Authors: Eric D Carlson, Marcin MajdaAbstract:TEMPO, 2,2,6,6-tetramethylpiperidnyl-1-oxy, is a weak surfactant exhibiting a reversible redox activity: a one-electron oxidation to its oxonium cation. In the course of our earlier work (ref. Wu et al. in J Am Chem Soc 127:4490–4496, 2005; Glandut et al. in J Phys Chem B 110:6101–6109, 2006; Glandut et al. in Langmuir 22:10697–10704, 2006), we developed a full understanding of TEMPO’s electrochemistry at line microband electrodes. In these experiments TEMPO diffuses to the line electrode residing in the plane of the air/water interface in two coupled media, bulk aqueous phase with D = 7.7 × 10−6 cm2/s and along the 2D air/water interface with at least an order of magnitude greater surface diffusion constant, Dsurf. The magnitude of the TEMPO oxidation current depends jointly on Dsurf and on the rate of surface partitioning expressed by the desorption rate constant, kdes. The population of TEMPO partitioned to the air/water interface is largely unsolvated and couples to the aqueous solution by hydrogen bonding to predominately one water molecule. Our experimental methodology allows us to simultaneously determine Dsurf and kdes by recording TEMPO voltammetric curves with line microband and barrier microband electrodes. In this report, we present a new methodology of producing and characterizing barrier microband electrodes using vapor-deposited SiO and introduce additional measures such as aspiration of the air/water interface designed to substantially reduce if not eliminate negative error due to surface impurities. These investigations generated a more accurate value of Dsurf of 1.0 ± 0.3 × 10−4 cm2/s which we discuss in terms of the dynamic properties of water in the air/water Interfacial Region.
-
electrochemical studies of the lateral diffusion of tempo in the aqueous liquid vapor Interfacial Region
2006Co-Authors: Nicolas Glandut, Andrew D Malec, Michael V Mirkin, Marcin MajdaAbstract:Surface partitioning and lateral mobility of TEMPO (2,2,6,6-tetramethyl-1-piperidynyloxy free radical) in the aqueous liquid/gas Interfacial Region were investigated electrochemically with 100 nm wide, 1.0 cm long microband electrodes positioned at the air/water interface. For redox active amphiphiles such as TEMPO, the electrochemical current is the sum of the surface and solution components representing the diffusive transport of TEMPO in both domains as well as the dynamics of equilibration at the air/water interface. Interpretation of the recorded current−voltage curves was aided by a FEMLAB simulation code developed to analyze transport processes in this class of systems. TEMPO and TEMPO+ partition constants (KT, KT+) and solution diffusivities (Dsol, equal for the two species) were obtained experimentally yielding KT = 5.0 ± 0.7 × 102 M-1, KT+ = 41 ± 3 M-1, and Dsol = 7.7 ± 0.35 × 10-6 cm2/s. In view of the low value of KT+, TEMPO+ was assumed not to partition to the air/water interface. We further ...
G. Harikrishnan - One of the best experts on this subject based on the ideXlab platform.
-
unraveling the polymer chain adsorbed constrained Interfacial Region on an atomistically thin carbon sheet
2019Co-Authors: Sanjay Kumar, Venkat Padmanabhan, Kishore Kumar Sriramoju, Vinod K. Aswal, G. HarikrishnanAbstract:Confinement of graphene and its functional derivatives in synthetic and biomacromolecules has been widely demonstrated recently to manifest in several multiscale phenomena in their mixtures. However, the intricate adsorbed Interfacial Region formed between polymer chains and a single layer of atomistically thin carbon sheet hitherto evaded an understanding of its nature and characteristics. Here, we reveal the structure of this constrained Region and estimate the thickness of the adsorbed polymer layer on a single layer of an atomistically thin graphene oxide sheet using both direct experiments and molecular dynamics simulations. We use small-angle neutron scattering on a model multicomponent mixture formed by an adsorbing polymer, graphene oxide, and solvent for revealing the structure of the constrained Interfacial Region. We quantify the intricate adsorbed polymer layer thickness on a single layer of atomistically thin graphene oxide sheet by Euclidean approximation of the experimentally observed self-similar Interfacial structure. The state of polymer chain random walk and influence of unadsorbed chains under experimental conditions are investigated and juxtaposed against the accuracy of this quantification. For long-chain polymers, the adsorbed layer thickness increases with increasing polymer molecular weight and shows a scaling relationship δ ∼ Rg0.22 with the polymer radius of gyration. For short-chain polymers, the thickness is nearly independent of molecular weight and shows a scaling relationship δ ∼ 0.6 Rg0.22. Coarse-grained molecular dynamics simulations performed on a model system similar to experiments qualitatively ratify the experimentally observed molecular weight-thickness relationship. Simulations show no discernible scaling relationship between radius of gyration and adsorbed layer thickness for low-molecular-weight polymers but show a consistent scaling δ ∼ Rg for high-molecular-weight polymers. A comparison between results from experiments and simulations indicates a discerning pathway in deciphering interface-governed multiscale phenomena in mixtures of adsorbing macromolecules with graphene and its functional derivatives.
-
Unraveling the Polymer Chain-Adsorbed Constrained Interfacial Region on an Atomistically Thin Carbon Sheet
2019Co-Authors: Sanjay Kumar, Venkat Padmanabhan, Kishore Kumar Sriramoju, Vinod K. Aswal, G. HarikrishnanAbstract:Confinement of graphene and its functional derivatives in synthetic and biomacromolecules has been widely demonstrated recently to manifest in several multiscale phenomena in their mixtures. However, the intricate adsorbed Interfacial Region formed between polymer chains and a single layer of atomistically thin carbon sheet hitherto evaded an understanding of its nature and characteristics. Here, we reveal the structure of this constrained Region and estimate the thickness of the adsorbed polymer layer on a single layer of an atomistically thin graphene oxide sheet using both direct experiments and molecular dynamics simulations. We use small-angle neutron scattering on a model multicomponent mixture formed by an adsorbing polymer, graphene oxide, and solvent for revealing the structure of the constrained Interfacial Region. We quantify the intricate adsorbed polymer layer thickness on a single layer of atomistically thin graphene oxide sheet by Euclidean approximation of the experimentally observed self-similar Interfacial structure. The state of polymer chain random walk and influence of unadsorbed chains under experimental conditions are investigated and juxtaposed against the accuracy of this quantification. For long-chain polymers, the adsorbed layer thickness increases with increasing polymer molecular weight and shows a scaling relationship δ ∼ Rg0.22 with the polymer radius of gyration. For short-chain polymers, the thickness is nearly independent of molecular weight and shows a scaling relationship δ ∼ 0.6Rg0.22. Coarse-grained molecular dynamics simulations performed on a model system similar to experiments qualitatively ratify the experimentally observed molecular weight–thickness relationship. Simulations show no discernible scaling relationship between radius of gyration and adsorbed layer thickness for low-molecular-weight polymers but show a consistent scaling δ ∼ Rg for high-molecular-weight polymers. A comparison between results from experiments and simulations indicates a discerning pathway in deciphering interface-governed multiscale phenomena in mixtures of adsorbing macromolecules with graphene and its functional derivatives
Hao Zhang - One of the best experts on this subject based on the ideXlab platform.
-
string like collective motion and diffusion in the Interfacial Region of ice
2017Co-Authors: Xinyi Wang, Hao Zhang, Xuhang Tong, Jack F DouglasAbstract:We investigate collective molecular motion and the self-diffusion coefficient Ds of water molecules in the mobile Interfacial layer of the secondary prismatic plane (112¯0) of hexagonal ice by molecular dynamics simulation based on the TIP4P/2005 water potential and a metrology of collective motion drawn from the field of glass-forming liquids. The width ξ of the mobile Interfacial layer varies from a monolayer to a few nm as the temperature is increased towards the melting temperature Tm, in accordance with recent simulations and many experimental studies, although different experimental methods have differed in their precise estimates of the thickness of this layer. We also find that the dynamics within this mobile Interfacial ice layer is “dynamically heterogeneous” in a fashion that has many features in common with glass-forming liquids and the Interfacial dynamics of crystalline Ni over the same reduced temperature range, 2/3 < T/Tm < 1. In addition to exhibiting non-Gaussian diffusive transport, decoupling between mass diffusion and the structural relaxation time, and stretched exponential relaxation, we find string-like collective molecular exchange motion in the Interfacial zone within the ice Interfacial layer and colored noise fluctuations in the mean square molecular atomic displacement 〈u2〉 after a “caging time” of 1 ps, i.e., the Debye-Waller factor. However, while the heterogeneous dynamics of ice is clearly similar in many ways to molecular and colloidal glass-forming materials, we find distinct trends between the diffusion coefficient activation energy Ea for diffusion Ds and the Interfacial width ξ from the scale of collective string-like motion L than those found in glass-forming liquids.We investigate collective molecular motion and the self-diffusion coefficient Ds of water molecules in the mobile Interfacial layer of the secondary prismatic plane (112¯0) of hexagonal ice by molecular dynamics simulation based on the TIP4P/2005 water potential and a metrology of collective motion drawn from the field of glass-forming liquids. The width ξ of the mobile Interfacial layer varies from a monolayer to a few nm as the temperature is increased towards the melting temperature Tm, in accordance with recent simulations and many experimental studies, although different experimental methods have differed in their precise estimates of the thickness of this layer. We also find that the dynamics within this mobile Interfacial ice layer is “dynamically heterogeneous” in a fashion that has many features in common with glass-forming liquids and the Interfacial dynamics of crystalline Ni over the same reduced temperature range, 2/3 < T/Tm < 1. In addition to exhibiting non-Gaussian diffusive transport, dec...
-
string like collective motion and diffusion in the Interfacial Region of ice
2017Co-Authors: Xinyi Wang, Hao Zhang, Xuhang Tong, Jack F DouglasAbstract:We investigate collective molecular motion and the self-diffusion coefficient Ds of water molecules in the mobile Interfacial layer of the secondary prismatic plane (112¯0) of hexagonal ice by molecular dynamics simulation based on the TIP4P/2005 water potential and a metrology of collective motion drawn from the field of glass-forming liquids. The width ξ of the mobile Interfacial layer varies from a monolayer to a few nm as the temperature is increased towards the melting temperature Tm, in accordance with recent simulations and many experimental studies, although different experimental methods have differed in their precise estimates of the thickness of this layer. We also find that the dynamics within this mobile Interfacial ice layer is “dynamically heterogeneous” in a fashion that has many features in common with glass-forming liquids and the Interfacial dynamics of crystalline Ni over the same reduced temperature range, 2/3 < T/Tm < 1. In addition to exhibiting non-Gaussian diffusive transport, decoupling between mass diffusion and the structural relaxation time, and stretched exponential relaxation, we find string-like collective molecular exchange motion in the Interfacial zone within the ice Interfacial layer and colored noise fluctuations in the mean square molecular atomic displacement 〈u2〉 after a “caging time” of 1 ps, i.e., the Debye-Waller factor. However, while the heterogeneous dynamics of ice is clearly similar in many ways to molecular and colloidal glass-forming materials, we find distinct trends between the diffusion coefficient activation energy Ea for diffusion Ds and the Interfacial width ξ from the scale of collective string-like motion L than those found in glass-forming liquids.
-
influence of string like cooperative atomic motion on surface diffusion in the 110 Interfacial Region of crystalline ni
2015Co-Authors: Hao Zhang, Ying Yang, Jack F DouglasAbstract:Although we often think about crystalline materials in terms of highly organized arrays of atoms, molecules, or even colloidal particles, many of the important properties of this diverse class of materials relating to their catalytic behavior, thermodynamic stability, and mechanical properties derive from the dynamics and thermodynamics of their Interfacial Regions, which we find they have a dynamics more like glass-forming (GF) liquids than crystals at elevated temperatures. This is a general problem arising in any attempt to model the properties of naturally occurring crystalline materials since many aspects of the dynamics of glass-forming liquids remain mysterious. We examine the nature of this phenomenon in the “simple” case of the (110) interface of crystalline Ni, based on a standard embedded-atom model potential, and we then quantify the collective dynamics in this Interfacial Region using newly developed methods for characterizing the cooperative dynamics of glass-forming liquids. As in our forme...
-
influence of string like cooperative atomic motion on surface diffusion in the 110 Interfacial Region of crystalline ni
2015Co-Authors: Hao Zhang, Ying Yang, Jack F DouglasAbstract:Although we often think about crystalline materials in terms of highly organized arrays of atoms, molecules, or even colloidal particles, many of the important properties of this diverse class of materials relating to their catalytic behavior, thermodynamic stability, and mechanical properties derive from the dynamics and thermodynamics of their Interfacial Regions, which we find they have a dynamics more like glass-forming (GF) liquids than crystals at elevated temperatures. This is a general problem arising in any attempt to model the properties of naturally occurring crystalline materials since many aspects of the dynamics of glass-forming liquids remain mysterious. We examine the nature of this phenomenon in the “simple” case of the (110) interface of crystalline Ni, based on a standard embedded-atom model potential, and we then quantify the collective dynamics in this Interfacial Region using newly developed methods for characterizing the cooperative dynamics of glass-forming liquids. As in our former studies of the Interfacial dynamics of grain-boundaries and the Interfacial dynamics of crystalline Ni nanoparticles (NPs), we find that the interface of bulk crystalline Ni exhibits all the characteristics of glass-forming materials, even at temperatures well below the equilibrium crystal melting temperature, Tm. This perspective offers a new approach to modeling and engineering the properties of crystalline materials.