Three-dimensional networks in bis(imidazolium) 2,2'-dithiodibenzoate and 4-methylimidazolium 2-[(2-carboxyphenyl)disulfanyl]benzoate.

Cocrystallization of imidazole or 4-methylimidazole with 2,2'-dithiodibenzoic acid from methanol solution yields the title 2:1 and 1:1 organic salts, 2C(3)H(5)N(2)(+).C(14)H(10)O(4)S(2)(2-), (I), and C(4)H(7)N(2)(+).C(14)H(10)O(4)S(2)(-), (II), respectively. Compound (I) crystallizes in the monoclinic C2/c space group with the mid-point of the S-S bond lying on a twofold axis. The component ions in (I) are linked by intermolecular N-H...O hydrogen bonds to form a two-dimensional network, which is further linked by C-H...O hydrogen bonds into a three-dimensional network. In contrast, by means of N-H...O, N-H...S and O-H...O hydrogen bonds, the component ions in (II) are linked into a tape and adjacent tapes are further linked by pi-pi, C-H...O and C-H...pi interactions, resulting in a three-dimensional network.