Structures of the Polymer Electrolyte Complexes PEO₆:LiXF₆ (X = P, Sb), Determined from Neutron Powder Diffraction Data

The crystal structures of the polymer electrolyte complexes PEO 6:LiPF 6 and PEO 6:LiSbF 6 have been obtained from powder diffraction data collected from deuterated molecules on the OSIRIS neutron powder diffractometer at ISIS, Rutherford Appleton Laboratory. The structures are similar to that recently reported for the PEO 6:LiAsF 6 complex and consist of rows of Li + ions encapsulated within columns formed by pairs of nonhelical PEO chains. The Li + ion is coordinated by five ether oxygens. The anions reside between the columns and are not coordinated to the Li + ions. Despite broad similarities, the structures do exhibit differences, and these differences are discussed.