Molecular evidence for the intermolecular S⋯S interaction in the surface molecular packing motifs of a fused thiophene derivative

A microscopic investigation of the molecular packing structures of a fused thiophene derivative reveals the important role of intermolecular S⋯S interaction in directing the 2D self-assembly. Thermal annealing of the assembly results in the irreversible phase transition to a new structure with different molecular trimeric packing motifs.