Crystal structure of 9,10-bis(1,3-dithiol-2-ylidene)-9,10-dihydroanthracene

The crystal structure of the well-studied 9,10-bis(1,3-dithiol-2-ylidene)-9,10-dihydroanthracene molecule, C₂₀H₁₂S4, (I), also known as exTTF, is reported. The molecular structure of (I) consists of a dihydroanthracene moiety with two 1,3-dithiol-2-ylidene substituents. This is a saddle-shaped molecule, which interacts with a close neighbor through various π-π and C - H⋯π contacts to form a 'dimer'. These 'dimers' interact through a series of C - H⋯S and C - H⋯π contacts to construct a complex three-dimensional extended structure.