A model of the optically active scheibe-aggregate of pseudoisocyanine

Principal Component Analysis of the Absorption Spectra of the Dye Thiacyanine in the Presence of the Surfactant AOT: Precise Identification of the Dye–Surfactant Aggregates

“…From this result it is obvious that the number of assuming the equilibrium scheme micelles containing THIA monomers is almost constant, and that each micelle has a definite capacity of accommodating 3 THIA / n AOT`THIA 3 AOT n ; a fixed number of monomeric dye molecules. It is also evident that the dye molecules, except associated with micelles, form metachromatic aggregates probably with free AOT k Å [THIA 3 AOT n ] [THIA] 3 1 [AOT] n , molecules; this would lead to a decrease in the micelle concentration with increase in THIA concentration, because to maintain the equilibrium between free AOT monomers and where n is the stoichiometric coefficient, for each value of micelles. Since the AOT concentration is kept constant at ization of (e a 1 e a ) gives two significant eigenvalues (the 4.0 mM, and the dye concentration as well as the concentrafirst four largest eigenvalues are 1.14 1 10 11 , 1.24 1 10 10 , tion of the metachromatic species is of the micromolar order, 1.01 1 10 6 , and 6.58 1 10 5 ) confirming the equilibrium the change in the micelle concentration with the formation coexistence of two absorbing species.…”

“…A ically bound to the polyanions (2,3). Similar spectral stock solution of THIA (0.20 mM) was prepared by dissolvchanges of many dyes caused by surfactants have also been ing 2.33 mg dye in 5.0 mL methanol, making up to 25 mL observed (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16), and these have also been interpreted as with water, and stored in the dark.…”

“…and Yamaoka (22); therefore, the concept of this method is e a Å l 1 e, [3] discussed here only briefly with some new idea. This method needs a set of observed overlapping spectra, measured by where f and l are linear combination coefficient matrices of varying the initial concentration of one or more of the comthe order (m 1 p) and e is the eigenvector matrix of the ponents present in equilibrium system containing more than order (p 1 n).…”

“…In most but also their molar absorption coefficients and equilibrium cases e is not a square matrix, and in that case both sides constant between either colored or the colored and colorless of Eqs. [2] and [3] are multiplied by e, the transpose of components can be determined simultaneously. From the set the matrix e, and then inverted as of, say m, overlapping spectra a data matrix d of the order (m 1 n) is constructed, whose element d ij (i Å 1 to m, j Å 1 to n) denotes the absorbance of the ith solution at the jth d 1 e Å f 1 (e 1 e) Å f 1 r, [4] wavelength.…”

Surface-Directed Adsorption in the Epitaxy Growth of Streptocyanine Dye Crystals

“…7 A herringbone structure was assumed in cases where two molecular orientations exist in one unit cell. 8 Such an arrangement was found by optical luminescence investigations of 1,1′-diethylpseudoisocyanine molecules adsorbed on silver halide single crystals. 9 However, due to the distorted structure of the dye, the determination of the exact molecule orientation remains to be difficult.…”