Anions for RTIL
[PF6]- for moisture stable, water immiscible IL
[BF4]- for moisture stable, but water miscible IL depending on the ratio of ionic liquid:water, system temperature, and alkyl chain length in the cation.
Less common anions include:
Triflate [TfO] Nonaflate [NfO] Bis(triflyl)amide [Tf2N]
CF3SO2- CF3(CF2)3SO2- (CF3SO2)2N-
Trifluoroacetate [TA] Heptafluorobutanoate [HB]