The crystal structures of 1-(polyfluorophenylmethyl)-3-methylimidazolium bromide salts

[Display omitted] •Crystal structures of four [1,3-RCH2NC3H3NMe]+.Br− salts (R = C6F4H and C6F3H2).•All possess C(1)H… Br− hydrogen bonding except that for R = 2,3,4,5-C6F4H.•All possess C(2)H… Br− hydrogen bonding.•All possess phenyl CH… Br− hydrogen bonding.•Structures for R = 2,3,5,6-C6F4H and 2,3,6-C6F3H2 possess Br−… π interactions. The crystal structures of 1-(2,3,5,6-tetrafluorophenylmethyl)-3-methylimidazolium bromide (2), 1-(2,3,4,5-tetrafluorophenylmethyl)-3-methylimidazolium bromide (3), 1-(2,4,6-trifluorophenylmethyl)-3-methylimidazolium bromide (4) and 1-(2,3,6-trifluorophenylmethyl)-3-methylimidazolium bromide (5) have been determined. The structures contain non-covalent interactions: hydrogen bonding, anion–π and π–π stacking interactions. The strengths of these interactions have been calculated using DFT. The structures and interactions are compared with those of 1-(2,3,4,5,6-pentafluorophenylmethyl)-3-methylimidazolium bromide (1) and 1-(2,6-difluorophenylmethyl)-3-methylimidazolium bromide (6).