Bulk synthesis and crystal structure of the first stage europium–graphite intercalation compound

A first stage binary graphite intercalation compound was synthesised in the lithium–europium–graphite system by direct immersion of a pyrolytic graphite platelet in a molten lithium-based alloy with a well chosen Li/Eu ratio at 350°C. The as-obtained bulk EuC6 compound exhibits mono-layered intercalated sheets of europium surrounded by two graphene sheets with a repeat distance equal to 487pm. The three dimensional study of the EuC6 crystal structure shows a hexagonal symmetry for this compound that crystallises in a P63/mmc space group with the following unit cell parameters: a=430pm and c=974pm.