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تسجيل مستخدم جديدNaphthalene crystal shape prediction from molecular dynamics simulations
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We used molecular dynamics simulations to predict the steady state crystal shape of naphthalene grown from ethanol solution. The simulations were performed at constant supersaturation by utilizing a recently proposed algorithm [Perego et al., J. Chem. Phys., 142, 2015, 144113]. To bring the crystal growth within the timescale of a molecular dynamics simulation we applied Well-Tempered Metadynamics with a spatially constrained collective variable, which focuses the sampling on the growing layer. We estimated that the resulting steady state crystal shape corresponds to a rhombic prism, which is in line with experiments. Further, we observed that at the investigated supersaturations, the ${00bar{1}}$ face grows in a two step two dimensional nucleation mechanism while the considerably faster growing faces ${1bar{1}0}$ and ${20bar{1}}$ grow new layers with a one step two dimensional nucleation mechanism.
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