| Abstract
| - Three different polarizable ion models for molten AgBr have been studied by molecular dynamics simulations.The three models are based on a rigid ion model (RIM) with a pair potential of the type proposed by Vashishtaand Rahman for α-AgI, to which the induced dipole polarization of the ions is added. In the first (PIM1) thedipole moments are only induced by the local electric field, while in the other two (PIM1s and PIM2s) ashort-range overlap induced polarization opposes the electrically induced dipole moments. In the PIM1 andthe PIM1s only the anions are assumed polarizable, while in the PIM2s both species are polarizable. Longmolecular dynamics simulations show that the PIM2s is an unphysical model since, for some improbable butpossible critical configurations, the ions become infinitely polarized. The results of using the PIM1, the PIM1s,as well as those of the simple RIM, have been compared for the static structure and ionic transport properties.The PIM1 reproduces the broad main peak of the total structure factor present in the neutron diffraction data,although the smoothed three-peak feature of this broad peak is slightly overestimated. The structural resultsfor the PIM1s are intermediate between those for the RIM and the PIM1, but fail to reproduce the experimentalfeatures within the broad principal peak. Concerning the ionic transport properties, the value of the conductivityobtained using PIM1 is in good agreement with experimental values, while the self-diffusion coefficients andthe conductivity for the PIM1s are lower than the corresponding values using the PIM1 and the RIM.
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