2,2 '-Bipyridinium bis(perchlorate)

The title compound, [H(2)bipy](ClO4)(2) or C10H10N22+. 2ClO(4)(-), was obta ined at the interface between an organic (2,2'-bipyridine in methanol) and an aqueous phase (perchloric acid in water). The compound crystallizes in s pace group P(1) over bar and comprises discrete diprotonated trans-bipyridi nium cations, [H(2)bipy](2+), and ClO4- anions. The cations and anions are connected through N-H . . .O and C-H . . .O hydrogen bonds [distances N . . .O 2.817 (4) and 2.852 (4) Angstrom, and C . . .O 3.225 (6)-3.412 (5)Angst rom]. The C-C bond distance between the two rings is 1.452 (5) Angstrom. Th e bipyridinium cation has a trans conformation and the N-C-C-N torsion angl e is 152.0 (3)degrees.