N,N'-Dithiobisphthalimide-1,4-dioxan (1/0.6): a C2/c solvate with disordered solvent molecules localized in channels

N,N'-Dithiobisphthalimide crystallizes from 1,4-dioxan solution as a solvate, 3C(16)H(8)N(2)O(4)S(2) x 1.8C(4)H(8)O(2), having space group C2/c. Four of the 12 C(16)H(8)N(2)O(4)S(2) molecules in the unit cell lie on twofold rotation axes, while the other eight lie in general positions. These molecules are linked by aromatic pi-pi-stacking interactions and by C[bond]H...O hydrogen bonds to form a framework enclosing continuous channels running parallel to the [101] direction, which account for ca 20% of the unit-cell volume. The dioxan molecules lie in these channels disordered across two sets of sites, with one set across an inversion centre and the other across a twofold rotation axis.