title: Push-pull bithienyl chromophore with an unusual transverse path of conjugation.
abstract: The synthesis, structure, and electronic properties of a novel cross-conjugated 10H-bisthienodithiocin-10-dicyanoethylene are reported. The X-ray single-crystal structure of the compound reveals a nonplanar conformation. The FT-IR and FT-Raman spectra of the compound show a great resemblance, which is a spectroscopic observation common to many push-pull systems. The UV-vis spectrum in CHCl3 displays a strong absorption at 370 nm accompanied by a shoulder at 430 nm so that the optical gap is 2.88 eV. On the other hand, the electrochemical gap amounts to 2.38 V. DFT and TDDFT quantum chemical calculations, at the B3LYP/6-31G** level, have been also performed to (i) determine the minimum-energy molecular structure, (ii) gain knowledge about the equilibrium atomic charges distribution, the topologies, and absolute energies of the frontier molecular orbitals around the gap and about the molecular vibrations which give rise to the most outstanding Raman bands experimentally evidenced, and (iii) to analyze the nature of the vertical one-electron excitations associated to the strongest UV-vis absorptions.
authors.affiliation: Department of Physical Chemistry, University of Málaga, Spain.
authors.forename: Rocío Ponce
authors.initials: RP
authors.lastname: Ortiz
authors.forename: Reyes Malavé
authors.initials: RM
authors.lastname: Osuna
authors.forename: Víctor
authors.initials: V
authors.lastname: Hernandez
authors.forename: Juan T López
authors.initials: JT
authors.lastname: Navarrete
authors.forename: Barbara
authors.initials: B
authors.lastname: Vercelli
authors.forename: Gianni
authors.initials: G
authors.lastname: Zotti
authors.forename: Víktor V
authors.initials: VV
authors.lastname: Sumerin
authors.forename: Elizabeth S
authors.initials: ES
authors.lastname: Balenkova
authors.forename: Valentine G
authors.initials: VG
authors.lastname: Nenajdenko
mesh_terms: D018360:Crystallography, X-Ray; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D011789:Quantum Theory; D012680:Sensitivity and Specificity; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D013059:Spectrum Analysis, Raman / Q000379:methods; D013457:Sulfur Compounds / Q000138:chemical synthesis* / Q000737:chemistry* / Q000302:isolation & purification; D013846:Thiepins / Q000138:chemical synthesis* / Q000737:chemistry*; D013876:Thiophenes / Q000138:chemical synthesis* / Q000737:chemistry*
chemical_list: C519085:10H-bisthienodithiocin-10-dicyanoethylene; D013457:Sulfur Compounds; D013846:Thiepins; D013876:Thiophenes