Aggregation of thiacyanine derivatives on polyelectrolytes

The molecular aggregation of pyronin Y in natural bentonite clay suspension

“…On the other hand, the aggregate states of PyY occurred as a result of electrostatic interaction between cationic dye and negatively charged clay minerals using the same concentration of the dye in the clay suspension, where the clay particles in aqueous solution were considered to be the driving force to induce molecular aggregation of PyY. This influence was observed on many dye molecules in the presence of other additives such as polymers, polyelectrolytes [16][17][18], nucleic acids [33] and colloidal particles [36] as well as clay particles [6]. Although PyY concentration was very low in the clay suspension for 0.1% CEC, the presence of intense aggregation originated from localized high dye concentration on the negatively charged clay particle surfaces [7,11,46].…”

“…The aggregation processes observed in different media are explained by the exciton theory [14,15]. Generally, the molecular aggregation occurs at higher dye concentrations in deionized water and at lower concentrations in the presence of some additives in the solution such as polyelectrolytes, polymers, colloidal nanoparticles [16][17][18] and on solid surfaces [19][20][21][22]. According to the exciton theory [14,15], there are two kinds of aggregates depending on molecular stacking in the aggregate units.…”

Fluorescence tuning of 2D montmorillonite optically active layers with beta-cyclodextrine/dye supramolecular complexes

“…Both of these aggregates can have parallel and anti-parallel molecular dipole orientation, in terms of their transition Applied Clay Science 114 (2015) 9-19 moments. The net dipole moment of anti-parallel orientations of both types of H-aggregates and J-aggregates with τ = 0°is zero, so the transition to these states is forbidden by symmetry rules (Peyratout and Dähne, 2002;Kang et al, 2010). However, the net dipole moment of aggregates with oblique alignment will differ from zero as τ ≠ 0°(Figure S1 electronic supplement).…”

Supramolecular Complexation of Sulfonated Aluminum Phthalocyaninеs and Chitosan in the Mixed Aqueous Solutions

“…There is a perception that the supramolecular complexes of polyelectrolytes with amphiphilic macrocyclic compounds were stabilized not only by electrostatic interactions, but also hydrophobic, π-π-interactions between small molecules. [17,40] The contribution of the non-electrostatic interactions, apparently, should decrease with decreasing capacity of macrocyclic compound to self-assembly in water. In our case the phthalocyanine, as noted above, has very low ability to self-association.…”