Solvatochromism of phenol blue in the ethyl acetate-acetic acid solvent system

Polarizability−Hyperpolarizability Influences upon Solvatochromism in Polychloroalkane and Polychloroalkene Media

“…The solvatochromic indicators, 2-nitro- p -toluidine, 2-nitro- p -anisidine, and Phenol Blue, were purified by reported methods, , and their purity was monitored by TLC. Spectral measurements were made with a Shimadzu UV-1201 instrument with a maximum wavelength uncertainty of ±0.3 nm.…”

“…The derived π* numbers were determined following the published procedures of Ulrich and Carr 8 and Laurence et al . and involved pairwise comparison checks between ν̄ max (1) vs ν̄ max (2) for the linearity of their respective bathochromic shifts. − The variance in the experimental π* data among the three indicators within a given solvent appeared to be random, and the overall uncertainty in values recorded in Tables and is ±0.04(SD).…”

“…By contrast to the extensive study of solvatochromism in aromatic media, observations concerning the dδ polarizabilities for the polychloroalkanes have been derived from a very limited number of solvents which have included both weak hydrogen bond donors as well as aprotic dipolar members. , This report now summarizes new and redetermined π* values for 24 monohalo- and polychloroalkanes, and these results are derived from the spectral shifts of three well-established solvatochromic indicators, i.e. 2-nitro- p -toluidine, 2-nitro- p -anisidine, and Phenol Blue. , From this enlarged data base, it is possible to reexamine the relationship between the apparent π* values for polychloroalkanes and their molecular dipole moments using a simple MO model for the perturbation arising from polarizability−hyperpolarizability effects within the reaction field of the solvent. The latter appears to be consistent with an approximately constant dδ contribution in eq 1 for the non-hydrogen-bonding polychloroalkanes as aprotic highly dipolar solvents.…”

Cation-Selective and Anion-Controlled Fluorogenic Behaviors of a Benzothiazole-Attached Macrocycle That Correlate with Structural Coordination Modes

“…The absolute quantum yield for L in acetonitrile was determined to be Φ = 0.83 (5.0 × 10 –4 M at 365 nm). As shown in Figure b, the single crystals of L exhibit a broad band with weak blue emission maxima at 425 and 450 nm (λ ex = 365 nm) arising from the intramolecular charge transfer. , …”

“…As shown in Figure 2b, the single crystals of L exhibit a broad band with weak blue emission maxima at 425 and 450 nm (λ ex = 365 nm) arising from the intramolecular charge transfer. 7,14 Selectivity for Metal Ions. The metal-sensing abilities of L were examined with several metal ions (Ag + , Hg 2+ , Co 2+ , Ni 2+ , Zn 2+ , Cd 2+ , and Pb 2+ ) by UV−vis and fluorescence spectroscopy in acetonitrile with respect to the cation-induced spectral changes.…”