The title compound, C25H14N4F6S2, is a new symmetric photo­chromic diaryl­ethene which can potentially be applied in optoelectronic devices, such as optical memories, photo switches, and color displays. In the crystalline phase, this mol­ecule, which has crystallographic twofold rotation symmetry, adopts an anti­parallel conformation that can undergo effective photocyclization reactions by a conrotatory mechanism. The distance between the two reactive C atoms is 3.642 (7) Å. The dihedral angle between the central cyclo­pentene ring and each thio­phene ring is 48.0 (2)°. The colourless crystals turn green when exposed to UV radiation and the process is reversible when exposed to visible light of appropriate wavelength.

The new title symmetric photochromic diaryl­ethene compound, C29H22F6S2, which contains a 3‐methyl­phenyl substituent, adopts an anti­parallel conformation in the crystal structure. The distance between the two reactive C atoms, i.e. the ring C atoms to which the methyl groups are attached, is 3.559 (8) Å. The dihedral angles between the central cyclo­pentene ring and the adjacent thio­phene rings are 40.8 (7) and 45.1 (5)°, and those between the thio­phene rings and the adjacent benzene rings are 3.3 (6) and 25.7 (9)°.