title: 3,3'-Dimethyl-1,1'-(butane-1,4-di-yl)diimidazolium bis-(tetra-fluoro-borate).
abstract: The title compound, C(12)H(20)N(4) (2+)·2BF(4) (-), was prepared by the anion exchange of a dibromide ionic liquid with sodium tetra-fluoro-borate. The asymmetric unit contains one half of the imidazolium cation, which lies about an inversion centre at the mid-point of the central C-C bond of the linking butyl chain. The two planar imidazole rings (r.m.s. deviation = 0.0013 Å) are strictly parallel and separated by 2.625 (7) Å [vertical distance between the centroids of two imidazole rings], giving the mol-ecule a stepped appearance. In the crystal structure, inter-molecular C-H⋯F hydrogen bonds link the cations and anions, generating a three-dimensional network.
authors.forename: Hao
authors.initials: H
authors.lastname: Geng
authors.forename: Ling-Hua
authors.initials: LH
authors.lastname: Zhuang
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.forename: Guo-Wei
authors.initials: GW
authors.lastname: Wang
authors.forename: Ai-Lin
authors.initials: AL
authors.lastname: Yuan