C acid) ionomer melts neutralized with lithium.42 When the temperature is high enough (600 K), they were able to observe the early stages of Li+ motion and rearrangements of ionic aggregates. For the partially neutralized ionomers where discrete clusters form, the ionic aggregates rearrange by a process of merging and breaking up, showing vehicular transport behavior. In the 100 neutralized ionomers where percolated ionic aggregates form, the ionomer chains remain pinned by the percolated aggregate for a long time, and Li+ motion follows the hopping mechanism.42 Size asymmetry introduced by mobile counterions with different sizes from that of the monomers affects ionic mobility, as demonstrated by coarse-grained MD simulations of a model random ionomer system, which is a single-ionconducting solid polymer electrolyte.43 The response to an external electric field simulates the charging process for such single-ion-conducting solid polymer electrolytes. Carrier Free Antibodies has been demonstrated that for ionomers with a high dielectric constant, having mobile counterions that have a bigger size mismatch (smaller than the charged groups on the polymer) results in higher ionic mobility, whereas for ionomers with relatively low dielectric constant, counterions with comparable sizes are preferred. Moreover, ion transport is found to be dominated by ion hopping instead of vehicular transport. Self-diffusion coefficients when the external field is absent offer insights into the discharging performance of solid polymer electrolytes. It is found that comparably sized counterions have the highest diffusion coefficient in ionomers with low dielectric constant and a nonmonotonic trend was observed in the diffusion coefficient of counterions in high dielectric constant ionomers where counterions with half the size as that of monomers showed the highest diffusion coefficient.43 These findings in the discharging performance of single-ion-conducting polymers were later corroborated by Bollinger et al., where they suggested that the electrostatic interaction needs to be strong enough to favor percolated aggregates but weak enough to facilitate ion dissociation for ion hopping to take place to improve conductivity.44 In addition to ion-containing polymer melts that can be utilized as single-ion conductors, salt-doped ion-containing polymers such as poly(ethylene oxide) (PEO) are a class of conventional polymer electrolytes. Fong et al. performed allatom MD simulations to study the transport properties of a model polyelectrolyte solution, poly(allyl glycidyl ether- lithium sulfonate) in dimethyl sulfoxide and observed a reduction in the diffusion length (L = 6D , where D is the solvent diffusion coefficient and is the residence time for two neighboring species to move together) as the Li+ concentration increases.45 Additionally, they showed that the Li+ transferencepubs.acs.org/JPCBPerspectivenumbers are surprisingly lower than previously estimated in experiments because the negatively charged polyion is responsible for the majority of the solution conductivity at all concentrations.45 Webb et al. demonstrated the suppression of ion and polymer motion at increasing salt concentrations of lithium hexafluorophosphate (LiPF6) in PEO using molecular dynamics (MD) simulations and a modified Rouse model.46 Wheatle et al. investigated how polymer polarity can influence the ionic conductivity of salt-doped polymer electrolytes using coarse-grained MD simulations.47 They have found.