title: Supramolecular self-assembly study of a flexible perylenetetracarboxylic diimide dimer in Langmuir and Langmuir-Blodgett films.
abstract: A novel perylenetetracarboxylic diimide molecule (2PDI-TAZ), which contains two perylenetetracarboxylic diimide (PDI) attached to a melamine headgroup, was designed and synthesized. Supramolecular self-assemblies were studied in Langmuir and Langmuir-Blodgett films. Surface pressure-area isotherm measurements and the spectroscopic studies indicate that the 2PDI-TAZ molecules adopted a face-to-face configuration and edge-on orientation in Langmuir or the multilayer LB films. The presence of the barbituric acid in subphase change the hydrophilicity of 2PDI-TAZ due to the hydrogen bonding between melamine and barbituric acid, which has been revealed by the pi-A isotherms and the FT-IR spectra. Transmission electron microscopy images of the LB films deposited from the barbituric acid solution revealed uniform nanowire morphology while the X-ray diffraction studies indicate that the molecules in the solid film packed with high order. The strong excimer emission of 2PDI-TAZ in LB films suggests enforced face-to-face configuration for the PDI unites in LB films in relative to that in solution.
authors.affiliation: College of Chemistry and Chemical Engineering, University of Jinan, Jinan 250022, China. chm_chenyl@ujn.edu.cn
authors.forename: Yanli
authors.initials: Y
authors.lastname: Chen
authors.forename: Ye
authors.initials: Y
authors.lastname: Kong
authors.forename: Yanfeng
authors.initials: Y
authors.lastname: Wang
authors.forename: Pan
authors.initials: P
authors.lastname: Ma
authors.forename: Meng
authors.initials: M
authors.lastname: Bao
authors.forename: Xiyou
authors.initials: X
authors.lastname: Li