Co-crystal formation with 1,2,3,5-dithiadiazolyl radicals.

The crystal structure of a novel dithiadiazolyl co-crystal, the second such co-crystal to be reported, has been determined, and is described in the context of the structures of the co-crystal formers. It is also shown that both known dithiadiazolyl co-crystals ([PhCN2S2][C6F5CN2S2] and [PhCN2S2][NC5F4CN2S2]) can be made via co-sublimation or by mixing co-crystal formers in solution, but not mechanochemically. DSC and theoretical calculations reveal that the thermodynamics of co-crystal formation in these systems is very finely balanced. [ABSTRACT FROM AUTHOR]