Structure of salt-free linear polyelectrolytes

The present level of understanding of charged polymer chains is far less than that of neutral chains. Since they pose difficult theoretical and experimental tasks, they especially warrant simulation studies. We performed molecular dynamics simulations on multichain systems of flexible chains full Coulomb interactions of the monomers and counterions are treated explicitly. This model produces osmotic pressure data that agree excellently to experiments and extend them. The chain conformation changes from stretched to coiled as the density increases to semidilute. The persistence lengths show discrepancies with the Odijk et al. wormlike chain picture.