Probability distributions of local order parameter p 2(i), calculated using 5 different values for the cutoff radius r p2.
Evolution of characteristic variables for a system of 336 n-eicosane chains during a typical MD simulation, after quenching from 400 to 250 K at t = 0. (a) Potential energy and volume per chain. (b) Size of the largest nucleus, n max, and the global orientation order parameter P 2.
The first-passage time of the largest nucleus size, n max, from one MD simulation of a system of 336 n-eicosane chains quenched from 400 to 250 K at t = 0. The open circles are simulation data, and the solid line is the formula of Eq. (10), with n*, τ*, and Z parameterized to fit the simulation data.
The probability distribution of τ*, n*, and Z, parameters obtained by fitting the first-passage time Eq. (10) to each of the 56 independent MD simulations: (a) τ* and the exponential fitting; (b) n* and the Gaussian fitting; (c) Z and the Gaussian fitting. A waiting time τ ′ = 10 ns was subtracted from τ* for the fitting and two systems that nucleate within τ ′ were excluded from all fittings.
The first-passage time of the largest nucleus size, n max, from one MD simulation of a system of 336 n-eicosane chains quenched from 400 to 250 K at t = 0, using three different parameter sets to define the crystal nucleus.
The free energy of formation for a crystal nucleus in a melt of 336 n-eicosane chains at 250, 265, and 280 K, respectively.
A snapshot of a crystal nucleus that consists of 130 united atoms from a MC simulation of a melt of 336 n-eicosane chains at 250 K: (a) end view, showing only those united atoms that are part of the nucleus; (b) side view, showing only those united atoms that are part of the nucleus; (c) side view, showing all united atoms belonging to chains that participate in the nucleus. United atoms in the crystal phase are black, while those in the melt phase are red.
The free energy of formation, the thickness and the radius as a function of nucleus size, n, for a crystal nucleus observed in a melt of 336 n-eicosane chains by Monte Carlo simulation at three different temperatures, (a) 250 K, (b) 265 K, and (c) 280 K. (+) = nucleus free energy from simulation; (Δ) = thickness l of nucleus; (◻) = radius r of nucleus. Two fitting schemes to the cylinder model Eq. (1) were used: dashed curve = two-parameter (σ e , σ s ) fitting and solid curve = three-parameter (σ e , σ s , ΔG v ) fitting.
Potential energy per chain and average density of n-eicosane systems at pressure P = 1 atm and several different temperatures.
The crystal nucleation free energy and critical nucleus size at several temperatures for an n-eicosane melt containing 336 chains.
Crystal-liquid interfacial free energy of n-eicosane molecules.
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