title: Small band gap oligothieno[3,4-b]pyrazines.
abstract: The synthesis and the optical and electrochemical properties of thiophene end capped oligo(2,3-alkylthieno[3,4- b]pyrazine)s are presented. The optical absorption rapidly shifts to lower energies with increasing chain length, caused in almost equal amounts by a rise of the HOMO and a lowering of the LUMO levels. The optical band gap of the polymer is estimated to be 1.13 +/- 0.07 eV. Extrapolated redox potentials indicate that the polymer is a small band gap p-type material.
authors.affiliation: Molecular Materials and Nanosystems, Eindhoven University of Technology, P.O. Box 513, NL-5600 MB Eindhoven, The Netherlands.
authors.forename: Bram P
authors.initials: BP
authors.lastname: Karsten
authors.forename: René A J
authors.initials: RA
authors.lastname: Janssen
mesh_terms: D004563:Electrochemistry; D015394:Molecular Structure; D010084:Oxidation-Reduction; D011719:Pyrazines / Q000138:chemical synthesis* / Q000737:chemistry*; D013237:Stereoisomerism; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D013876:Thiophenes / Q000737:chemistry
chemical_list: D011719:Pyrazines; D013438:Sulfhydryl Compounds; D013876:Thiophenes