TY - JOUR AU - Weldeab, Asmerom O.; Kornman, Cory T.; Li, Lei; Starkenburg, Daken J.; Zhao, Xueying; Fagnani, Danielle E.; Sadovy, Sara J.; Perry, Scott S.; Xue, Jiangeng; Castellano, Ronald K. TI - Structure–Assembly–Property Relationships of Simple Ditopic Hydrogen-Bonding-Capable π-Conjugated Oligomers SN - 2625-1825 PY - 2021 JF - Organic Materials LA - EN VL - 03 IS - 02 SP - 390 EP - 404 DA - 2021/08/25 ET - 2021/06/22 KW - conjugated molecules KW - hydrogen bonding KW - organic monolayers KW - optoelectronic properties KW - self-assembly KW - supramolecular chemistry AB - A series of simple ditopic hydrogen-bonding-capable molecules functionalized with 2,4-diamino-1,3,5-triazine (DAT), barbiturate (B), and phthalhydrazide (PH) on both termini of a 2,2′-bithiophene linker were designed and synthesized. The intrinsic electronic structures of the ditopic DAT, PH, and B molecules were investigated with ground-state density functional theory calculations. Their solution absorbance was investigated with UV-vis, where it was found that increasing size of R group substituents on the bithiophene linker resulted in a general blue-shift in solution absorbance maximum. The solid-state optical properties of ditopic DAT and B thin films were evaluated by UV-vis, and it was found that the solid-state absorbance was red-shifted with respect to solution absorbance in all cases. The three DAT molecules were vacuum-thermal-deposited onto Au(111) substrates and the morphologies were examined using scanning tunneling microscopy. (DAT-T)2 was observed to organize into six-membered rosettes on the surface, whereas (DAT-TMe)2 formed linear assemblies before and after thermal annealing. For (DAT-Toct)2, an irregular arrangement was observed, while (B-TMe)2 showed several co-existent assembly patterns. The work presented here provides fundamental molecular–supramolecular relationships useful for semiconductive materials design based on ditopic hydrogen-bonding-capable building blocks. PB - Georg Thieme Verlag KG DO - 10.1055/a-1534-1508 UR - http://www.thieme-connect.com/products/ejournals/abstract/10.1055/a-1534-1508 ER -