The structure of liquid 1-alkyl-3-methylimidazolium bromides – a combined high-energy X-ray diffraction and molecular dynamics study

The structures of 1-ethyl-3-methyllimidazolim bromide(EMIMBr)and 1-hexyl-3-methylimidazolium bromide were investigated by a combination of high-energy X-ray diffraction and molecular dynamics simulation. The ion organization in liquid EMIMBr differs noticeably from the crystal structure just above the melting point, and a distinct intermediate-range ordering is observed due to the aggregation of aliphatic chain upon increase of its length.