Crystal structure of an ionic charge-transfer complex of DAP-F(4)TCNQ (DAP=1,6-diaminopyrene, F(4)TCNQ=2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-p-quinodimethane)

A charge-transfer complex of DAP with F(4)TCNQ has been obtained by electro chemical reduction of F4TCNQ in acetonitrile in the presence of DAP . BF4. The crystal comprises segregated one-dimensional columns of donors and acce pters with CH3CN as the crystal solvent. The molecular geometry and infrare d spectrum show that the donor and acceptor components are completely ioniz ed. These features are the same as those found in DAP.TCNQ. However, a mark ed difference lies in the column structure; both the DAP and F4TCNQ columns are composed of the dimerized units, while they are uniform in DAP.TCNQ. T he difference can be accounted by the increase of the transfer energy in DA P .F(4)TCNQ . CH3CN compared with DAP.TCNQ.