A series of Molecular Dynamics simulations are used to probe the structural features of the 1-alkyl-3-methylimidazolium hexafluorophosphate ionic liquid family [CnC1im][PF6] (n = 3, 6, 9, 12). The structural analysis results — structure factor functions, pair radial distribution functions, and aggregate analyses — are compared with previous results obtained for the well-known [CnC1im][NTf2] series. Equimolar mixtures of ([CmC1im][PF6] + [CnC1im][PF6]) with m/n = 3/9, 3/12, 6/9 and 6/12 are also studied and their structure is investigated using the same analysis techniques.