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The monolayers at the air/water interface, the Langmuir-Blodgett (LB) monolayers and multilayers on solid substrates of five kinds of europium bisphthalocyanines EuPc2 (Eu1), EuPc[Pc(OC5H11)8)] (Eu2), EuPc[Pc(C7H15)8] (Eu3), Eu[Pc(OC5H11)8)]2 (Eu4) and Eu[Pc(C7H15)8]2 (Eu5) were characterized by using π–A isotherms, UV-vis spectra, polarized UV-vis spectra, low-angle X-ray diffraction (LAXD) and transmission electron microscopy (TEM). The results demonstrate that the different molecular structures have great influence on the orientation of the macrocycles, on the configuration of the molecules and on the organization of the supramolecular assemblies at the air/water interface. In the aggregates of Eu1 molecules, the macrocycles stack closely in a face-to-face mode with an orientation angle of 51°. Eu2 and Eu4 form homogeneous monolayers at a lower surface pressure due to the stronger hydrophilicity of the substituents, in which the molecules take the face-on configuration with the Pc rings in contact with the water surface. The orientation angles are ca. 45° and 30°, respectively, and the chains extend to the air. Eu5 molecules take an edge-on configuration with the ring orientation angle of ca. 30° at the air/water interface form rod-like supramolecular structures. Eu3 does not form an ordered structure at the air/water interface due to the asymmetric molecular structure. [Copyright &y& Elsevier]

The supramolecular assemblies of sandwich-type complex Eu(TPyP)Pc (TPyP: tetrapyridylporphyrin; Pc: phthalocyanine) were fabricated at the air/water and air/Cd2+ aqueous solution interfaces. One-dimensional columns and two-dimensional coordinate framework were formed, respectively, and characterized by surface pressure–area (π–A) isotherms, UV–vis spectra and polarized UV–vis spectra. The orientation angle of macrocycles with respect to the substrate surface is about 38° and 32° for the Langmuir–Blodgett films from pure water and Cd2+ subphase surfaces, respectively. [Copyright &y& Elsevier]

Abstract: Molecular assemblies and nanoparticles of chiral coordination polymers composed of connector of K2PdCl4 and linkers of bisdentate binaphthyl-bis(amidopyridyl) (BNBAPy) ligands have been constructed at the air–water interface. The chiral S- and R-BNBAPy ligands showed similar surface pressure–area isotherms on the K2PdCl4 subphase surface, with the limited molecular area of about 1.2nm2, which suggested that the ligands were nearly parallel to the subphase surface. The X-ray photoelectron spectra for the Langmuir–Blodgett (LB) films of the coordination polymers revealed that the films were composed of Cl, C, Pd and N elements. These Pd-(R-/S-)BNBAPy coordination polymers formed round nanoparticles at the interface with average diameters of 15–20nm. It was found that the chirarity of ligands was almost remained in the LB films of Pd-(R-/S-)BNBAPy coordination polymers, indicating there was little influence on the orientation or arrangement of the ligand chiral center after the formation of their coordination polymer LB films. The present method could provide a facile way to construct chiral molecular and nanostructural materials. [Copyright &y& Elsevier]

Abstract: Ternary europium complexes were formed at the air–water interface mediated by monolayers of 4,4′-dinonyl-2,2′-dipyridyl (DNDPy) and 4′-(4-methylphenyl)-2,2′:6′,2″-terpyridine (MPTPy). A saturated Eu(TTA)3 (TTA: theonyltrifluoroacetone) aqueous solution was used as subphase, on the surface of which condensed DNDPy and MPTPy monolayers could be stabilized. The DNDPy-/MPTPy–Eu(TTA)3 layers were transferred onto either hydrophobic or hydrophilic substrate surfaces by Langmuir–Blodgett (LB) method. Fluorescence spectra showed several sharp peaks corresponding to Eu3+ emissions from 5D1 → 7F1 (535nm) and 5D0 → 7F0,1,2,3 (580, 595, 612 and 650nm). A relative stronger emission from 5D1 → 7F1 to that from 5D0 → 7F2 was recorded for the LB films of DNDPy–Eu(TTA)3 complex. Compared with that in solution, longer fluorescence lifetime was observed for the complexes in the LB films. [Copyright &y& Elsevier]