A Donor–Acceptor–Donor Structured Organic Conductor with S···S Chalcogen Bonding

A novel
thiophene derivative 7,9-di­(thiophen-2-yl)-8H-cyclopenta­[a]­acenaphthylen-8-one
(DTCPA) is shown to exhibit
high electrical conductivity (1.97 × 10–2 ±
0.0018 S/cm at RT) in the crystalline state. The material shows two
orders of increase in conductivity from normal solid to single crystalline
state. The crystal structure has S···S chalcogen bonding,
C–H···O hydrogen bonding, and π···π
stacking as the major intermolecular interactions. The nature and
strength of the S···S interactions in this structure
have been evaluated by theoretical charge density analysis, and its
contribution to the crystal packing quantified by Hirshfeld surface
analysis. Further, thermal and morphological characterizations have
been carried out, and the second harmonic generation (SHG) efficiency
has been measured using the Kurtz–Perry method.