Details

Autor(en) / Beteiligte

• Tolbin, Alexander Yu
• Savelyev, Mikhail S.
• Gerasimenko, Alexander Yu
• Sedova, Marina V.
• Maklakov, Sergey S.
• Pushkarev, Victor E.

Titel

The effect of covalent binding of phthalocyanine macrocycles with a cyclotriphosphazene spacer on the aggregation, NLO, and CT properties

Ist Teil von

• Journal of porphyrins and phthalocyanines, 2023-01, Vol.27 (1n04), p.241-252

Ort / Verlag

Singapore: World Scientific Publishing Company

Erscheinungsjahr

2023

Beschreibungen/Notizen

• This work is devoted to studying the aggregation effect on the nonlinear optical (NLO) and charge transport (CT) properties of low-symmetry phthalocyanines bearing a cyclotriphosphazene moiety, a monomer, and clamshell-type bis-phthalocyanine. FE-SEM and AFM studies revealed ordered nanoaggregation in these compounds, represented as repeating objects of regular configuration, globules (340–480 nm), which contain small aggregates inside their cavity, similar to smoothed polygons (ca. 40 nm). Such specificity is not characteristic of other functionalized phthalocyanines, which we dealt with earlier. A new spectral method for estimating the aggregation threshold based on the change in extinction with increasing concentration of solutions was also implemented, and the effect of aggregation on optical limiting was demonstrated. The behavior of isomers and rotamers of bis-phthalocyanine in the presence of electric fields of various strengths was investigated with the DFT calculations, and that partially corresponds to the impact of laser radiation on molecules. It was shown that the unusual behavior of the trans-isomer in FF-DFT calculations is the reason for the worsening of the NLO and CT characteristics of bis-phthalocyanine, in which the macrocycles are strapped through a phosphazene spacer. An advanced method of multiparametric analysis has been implemented to evaluate the NLO and CT properties of the dyes in general. A clamshell-type bis-phthalocyanine ligand with the macrocycles strapped through a cyclotriphosphazene moiety was synthesized, and the aggregation was investigated in comparison with the corresponding monomer. The influence of aggregation on the NLO and CT properties is demonstrated, and a parametric pattern between these properties was found.