Structural investigations into a new polymorph of F4TCNQ: towards enhanced semiconductor properties

During the course of research into the structure of 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F 4 TCNQ), C 12 F 4 N 4 , an important compound in charge-transfer and organic semiconductor research, a previously unreported polymorph of F 4 TCNQ was grown concomitantly with the known polymorph from a saturated solution of dichloromethane. The structure was elucidated using single-crystal X-ray diffraction and it was found that the new polymorph packs with molecules in parallel layers, in a similar manner to the layered structure of F 2 TCNQ. The structure was analysed using Hirshfeld surface analysis, fingerprint plots and pairwise interaction energies, and compared to existing data. The structure of a toluene solvate of F 4 TCNQ is also reported.