Snapshots of the structure of [C_nmim][PF₆] for n = 2–12 (from left to right). Polar domains: anion + cation imidazolium ring (red); nonpolar domains: cation alkyl chain (green). When n = 2, small and globular apolar “islands” form within the continuous polar network. An increase of the alkyl chain length (n = 6, 8, 12) enables hydrocarbon domains to interconnect in a bicontinuous, sponge-like nanostructure. [C₄mim][PF₆] marks the transition between the two solvent morphologies. Reprinted with permission from Ref. [35]. Copyright 2006, American Chemical Society.