Small-angle X-ray scattering and neutron reflectivity studies of Langmuir–Blodgett films of copper tetra-tert-butyl-azaporphyrines

Abstract

Langmuir-Blodgett (LB) films of tetra-tert-butyl-substituted copper azaporphyrines, namely phthalocyanine (CuPc'), tetra-3-nitrophthalocyanine (CuPc*) and porphyrazine (CuPaz'), are studied by small-angle scattering technique. Two kinds of systems are under investigation: first, the CuPc'/Cd-stearate-d 35 superlattices; second, the LB films of CuPc', CuPc* and CuPaz' doped with benzene-d 6. X-ray diffraction patterns of the superlattices exhibit bilayer structural units indicating existence of not only 1D but also 3D nano-aggregates of CuPc'. The neutron reflectivity study on the films heavily doped with benzene-d 6 indicates that π-deficiency and size of the azaporphyrine nuclei favor interactions between the nano-aggregates.

Nanoaggregates in floating layers of azaporphyrins

“…It should be noted that, distinct of tetra-(5-nitro-3-tert-butyl) copper phthalocyanine, which has more diverse array of formed edge-on states [21], the copper phthalocyanine studied in the present paper (without nitro groups) forms only three different edge-on structures: β-, χ-, and o-forms. The first two are found in bulk samples of phthalocyanines, while the last-named, the "overshifted" o-form, was for the first time found by us in A 1 B 1 copper tetratert-butylphthalocyanine -Cd-stearate superlattice [31]. Moreover, the CuPctBu4 floating monolayer consists of homogenous microaggregates 200-400 μm long, in contrast to porphyrazin layers comprising 3-5 μm microaggregates.…”

“…1) and copper tetrabenzotriazaporphyrine (CuPcThptBu4). CuPtBu4 has also been chosen because the structure [30,31] and properties [32] of its LB films were studied earlier.…”

Atypical Film‐Forming Behavior of Soluble Tetra‐3‐Nitro‐Substituted Copper Phthalocyanine

“…Initially, the glass‐supported LS film prepared from the over‐compressed monolayer and treated earlier with benzene‐d6 was taken. Because this film exhibited very low penetrability for benzene molecules, the novel NR data were analyzed by the multi‐layer model properly adjusted.…”

Formation and Study of Nanostructured M-Monolayers and LS-Films of Triphenylcorrole

“…[10] One of today's emerging trends is focused on creation of thin-film organic materials, including based on corroles, [11][12][13][14][15][16][17][18][19][20] especially those, where structural and functional units are represented by 2D and 3D nanoparticles. [21,22] First supermolecules of macroheterocyclic compounds were obtained. [16][17][18] Thin films of corroles can be obtained in different ways, including vacuum sublimation, solution casting, and Langmuir-Blodgett techniques (LB).…”