Molecular Dynamics Simulation of Molten Alkali Nitrates

Abstract

Molecular dynamics (MD) simulations have been performed for several pure alkali nitrate melts. Special attention was paid to the examination o f the interaction potential: macroscopic quantities like pressure were calculated and compared with real values. To improve the results the commonly used potential for alkali nitrates (Coulomb pair potential and Born-type repulsion) has been extended by a short-range-attraction term to meet the real behaviour o f the liquid.With these improved potentials, simulations of pure L iN 0 3, N a N 0 3, K N 0 3, and R b N 0 3 have been performed with special regard to the influence of size and mass o f the cations on the transport effects to show analogies to isotope effects. The calculated self diffusion coefficients (SDC) have been compared to results obtained with the NMR spin echo method.

Development of a Polarizable Interatomic Potential for Molten Lithium, Sodium, and Potassium Nitrate

“…In this study, cation diffusion coefficients decrease with increased size and mass. A similar trend in cation self-diffusion has been shown in a prior molecular dynamics study, 42 where it was demonstrated that the diffusion coefficient was insensitive to the cations mass and sensitive to the ionic radius. Nevertheless, the cause of the discrepancy between the simulated Na + cations observed here and the experimental observation remains unexplained.…”

Molecular Simulation of the Thermal and Transport Properties of Three Alkali Nitrate Salts

“…They introduced a flexible model for the nitrate anion. Vohringer and Richter modified the intermolecular parameters for the alkali nitrate salts and were able to get better results for self-diffusivities using this modified model. Ribeiro studied the composition dependence of ionic mobilities in mixtures of two cations with a common anion .…”

Structural Analysis of Molten NaNO3by Molecular Dynamics Simulation

“…Adya et al for the first time investigated the microscopic atomic configuration and diffusion in molten NaNO 3 by means of X-ray diffraction measurement and molecular dynamics (MD) simulation, and compared its partial structure factors and partial pair distribution functions with those of molten NaNO 2 and the eutectic mixture of the NaNO 3 -NaNO 2 system showed good additivity for the intermolecular structure because the ionic radius of NO 3 and NO 2 ions are similar owing to the presence of a lone pair on the nitrite ion [6]. After Adya et al [6], several researchers have reported the MD simulation results of molten alkali nitrates [7][8][9][10][11][12]. For example, Kato et al have reported cation dependence of the detailed structural features and ionic dynamics in molten alkali nitrates [11].…”