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Competitive B2 and B33 Nucleation during Solidification of Ni 50 Zr 50 Alloy: Molecular Dynamics Simulation and Classical Nucleation Theory
We studied the homogenous nucleation of the stoichiometric B2 and B33 phases in the Ni 50 Zr 50 alloy using the persistent embryo method and the classical nucleation theory. The two phases become very close competitors at large supercoolings, which is consistent with the experimental observations. In the case of the B2 phase, the linear temperature dependence of the solid–liquid interface (SLI) free energy extrapolated to the melting temperature leads to the same value as the one obtained from the capillarity fluctuation method (CFM). In the case of the B33 phases, the SLI free energy is also a linear function of temperature at large supercoolings, but the extrapolation to the melting temperature leads to a value which is considerably different from the CFM value. This is persistent with the large anisotropy of the SLI properties of the B33 phase nearby the melting temperature observed in the simulation of the nominally flat interface migration.
Molecular Dynamics Simulations of Ion-Containing Polymers Using Generic Coarse-Grained Models
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Uncovering Local Correlations in Polymer Electrolytes by X-ray Scattering and Molecular Dynamics Simulations
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Molecular Dynamics Simulations of the Effects of Entanglement on Polymer Crystal Nucleation
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Unique Phase Behavior of Inverse Tapered Block Copolymers: Self-Consistent Field Theory and Molecular Dynamics Simulations
Using theory and simulation, we study the microphase separated structures of inverse tapered block copolymers. These are AB block copolymers with a gradient region inserted between the pure A and B blocks that smoothly changes in composition from B to A, with the B-side of the taper bonded to the pure A block. Tapering is a means to increase miscibility between polymer blocks, and by controlling the length of the taper, the phase behavior and domain spacing can be adjusted. As opposed to better known ABAB tetrablock copolymers that also have four alternating A-rich and B-rich regions, here the intermediate region has a partially mixed composition, promoting relatively diblock-like behavior for shorter inverse tapers or low segregation strength but unique behavior as a function of increasing segregation strength for some systems. In particular, for systems in which 50% of the backbone is the taper, the larger of the two pure end blocks - composed of the overall majority component - can phase separate analogously to the minority component of a diblock copolymer, creating cylinder and network phases in which the majority component’s pure block is the minority phase in a matrix of a relatively disordered mixture of the tapered region and the minority component’s pure block.
Growth Mechanism and Kinetics of Diamond in Liquid Gallium from Quantum Mechanics Molecular Dynamics Simulations
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Development of Density-Functional Tight-Binding Parameters for the Molecular Dynamics Simulation of Zirconia, Yttria, and Yttria-Stabilized Zirconia
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Water Networks in Photosystem II Using Crystalline Molecular Dynamics Simulations and Room-Temperature XFEL Serial Crystallography
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