title: 4,4'-Di-tert-butyl-2,2'-dipyridinium dichloride.
abstract: In the title compound, C(18)H(26)N(2) (2+)·2Cl(-), the complete dication is generated by crystallographic inversion symmetry; both N atoms are protonated and engaged in strong and highly directional N-H⋯Cl hydrogen bonds. Additional weak C-H⋯Cl contacts promote the formation of a tape along ca. [110]. The crystal structure can be described by the parallel packing of these tapes. The crystal studied was a non-merohedral twin with twin law [-1 0 0, 0 -1 0, -0.887 0.179 1] and the final BASF parameter refining to 0.026 (2) .
authors.affiliation: Department of Chemistry, University of Aveiro, CICECO, 3810-193 Aveiro,  Portugal.
authors.forename: Tatiana R
authors.initials: TR
authors.lastname: Amarante
authors.forename: Isabel S
authors.initials: IS
authors.lastname: Gonçalves
authors.forename: Filipe A
authors.initials: FA
authors.lastname: Almeida Paz
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