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