Specific ion effects in surfactant solutions affect the properties of micelles. Dodecyltrimethylammonium chloride (DTAC), bromide (DTAB), and methanesulfonate (DTAMs) micelles are typically spherical, but some organic anions can induce shape or phase transitions in DTA(+) micelles. Above a defined concentration, sodium triflate (NaTf) induces a phase separation in dodecyltrimethylammonium triflate (DTATf) micelles, a phenomenon rarely observed in cationic micelles. This unexpected behavior of the DTATf/NaTf system suggests that DTATf aggregates have unusual properties. The structural properties of DTATf micelles were analyzed by time-resolved fluorescence quenching, small-angle X-ray scattering, nuclear magnetic resonance, and electron paramagnetic resonance and compared with those of DTAC, DTAB, and DTAMs micelles. Compared to the other micelle types, the DTATf micelles had a higher average number of monomers per aggregate, an uncommon disk-like shape, smaller interfacial hydration, and restricted monomer chain mobility. Molecular dynamic simulations supported these observations. Even small water-soluble salts can profoundly affect micellar properties; our data demonstrate that the -CF3 group in Tf(-) was directly responsible for the observed shape changes by decreasing interfacial hydration and increasing the degree of order of the surfactant chains in the DTATf micelles.

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Two phenothiazine-based polymerstetraphenylethylene-(PTzTPE) and triphenylacrylonitrile-substituted (PTzTPAN) polyphenothiazineswere studied in organic solvents, solid state, and THF:water and dioxane:water mixtures to investigate the occurrence of aggregation-induced emission (AIE). It is shown that AIE is present for the PTzTPE and PTzTPAN polymers in THF:water mixtures, although to a lesser extent in the latter case. The emission of PTzTPE was found to display the simultaneous emission of locally excited (LE) and charge transfer (CT) states with emission maxima at ∼480 and ∼640 nm, respectively. Dynamic light scattering measurements in THF:water mixtures point out to the formation of small nanoaggregates in which the polymers likely adopt a collapsed structure. The overall effect of the restriction of molecular movements of TPE or TPAN units and the poly(phenothiazine) backbone (thus leading to the enhancing of the excited state radiative channel over the internal conversion deactivation channel through the reduction of the "loose bolt" or free rotor effect), together with the decrease of the CT contribution with the increase of the water fraction was associated with the AIE effect observed in THF:water mixtures. For PTzTPE in dioxane:water mixtures an opposite effect, i.e., an aggregation caused quenching (ACQ), is observed with the increment of water fraction, f w , in the mixture (ϕ F decreasing from 0.14 in pure dioxane to 0.042 for f w = 90%). This selective AIE behavior in specific solvents was attributed to the conversion of emissive LE states into dark CT states. DFT calculations of the phenothiazine-TPE and -TPA trimer units confirm the bent butterfly shape generally adopted by the phenothiazine moiety and the excited state charge transfer from the phenothiazine donor to the sidechain acceptor units.

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The search for a unique molecular system able to efficiently emit in the total visible range of the electromagnetic spectra, i. e., white light emission (WLE), is a topic of intense research. We here show that aggregates formed by diphenylbenzofulvene (DPBF) derivatives are from two to four orders of magnitude more emissive than their monomers. From a simple strategy, involving structural modification of a DPBF propelled shape core, a close match with the pure white light emission coordinates is obtained with a combination of two derivatives in films, with featured solid‐state emission, without involvement of D−A groups or energy transfer processes.