Molecular dynamics simulation of the structure of PEO based solid polymer electrolytes

A water-free solid polymer electrolyte containing poly(ethyle oxide) (PEO) and poly(ethyle oxide) with sulfonic acid dianion end groups (PEO sulfonic acid dianion) is constructed using periodic boundary conditions by atomisti c molecular modelling. The vibrational frequencies are calculated and found to be in agreement with the measured spectra. The structure of the PEO sul fonic acid dianion is studied by calculating the dihedral angle distributio ns and the intramolecular pair correlation functions between the carbon ato ms and the ether oxygen atoms. The dimensional analysis is made. Results co ncerning the PEO sulfonic acid dianion in the water-free system are compare d to the results obtained in the water containing systems and in vacuum. Th e structure of the PEO sulfonic acid dianion in water-free system is found to be rather similar to its structure in water and PEO containing system bu t different from its structure in vacuum. (C) 2000 Elsevier Science Ltd. Al l rights reserved.