The geometry and structural properties of the 4,8,12-trioxa-4,8,12,12c-tetrahydrodibenzo[cd,mn]pyrene system in the cationic state. Structures of a planar organic cation with various monovalent and divalent anions

The geometry of the 4,8,12-trioxa-4,8,12,12c-tetrahydrodibenzo[cd,mn]pyrene system in the cationic state was established by X-ray structural resolutio n of the salts formed between the cation and various anions. The geometry w as found to be planar for the 4,8,12-trioxa-4,8,12,12c-tetrahydrodibenzo [c d,mn]pyrenylium and 2,6,10-tri(tert-butyl)-4,8,12-trioxa-4,8,12,12c-tetrahy drodibenzo[cd,mn]pyrenylium cations with the monovalent anions I-, BF4-, PF 6- AsF6-, HNO3. NO3- and CF3SO3-, and the divalent anions S2O62- and Mo6Cl1 42-. The salts were found to crystallize in distinct space groups following a characteristic pattern. Mixed cation-anion stacking resulted in space gr oups with high symmetry: Pbca in three cases and R (3) over bar c in one; a temperature study of the latter was made at ten different temperatures. Th e formation of dimers of anions and cations resulted in lower-symmetry spac e groups, mainly monoclinic (P2(1)/n, P2(1)/c and C2/c), but also P (1) ove r bar.