Twisted intramolecular charge transfer (TICT) is one of the hot points in condensed phase photochemistry at the present time. Most of the studies on TICT up to now, however, are performed in organic medium, which lead...Twisted intramolecular charge transfer (TICT) is one of the hot points in condensed phase photochemistry at the present time. Most of the studies on TICT up to now, however, are performed in organic medium, which leads to a correlation that the intensity ratio of the long-wavelength TICT fluorescence band (a band) to shortwavelength normal fluorescence band (b band), I_a/I_h, increases with the medium polarity. It is unknown whether such a correlation is applicable to aqueous solution or it is in the transition from organic solvent through water. Thus a systematic study of TICT in aqueous solution and its comparison with that in organic medium are significant for the development and deepening of the theory and application of TICT. In the present note, a steady-state fluorescence spectroscopic study of TICT of p-N, N-dimethylaminobenzoic acid (DMABOA) in aqueous cetyltrimethylammonium chloride (CTMAC) micellar solution is described.展开更多
Synchronous fluorometry can cause a band-narrowing effect to improving the fluorometric selectivity (Fig. 1). However, since the △λ value selected is usually small (generally about 0—5 nm) in synchronous scanning, ...Synchronous fluorometry can cause a band-narrowing effect to improving the fluorometric selectivity (Fig. 1). However, since the △λ value selected is usually small (generally about 0—5 nm) in synchronous scanning, the interference of solvents scattering light (mainly Rayleigh scattering light) is so serious that the sensitivity and the detection limit are harmed greatly.展开更多
The microenvironmental effects of β-cyclodextrin (β-CD) on the twisted intramolecular charge transfer (TICT) of ρ-N, N-dimethylaminobenzaldehyde (DMABA) are investigated using fluorescence spectroscopy. The typical...The microenvironmental effects of β-cyclodextrin (β-CD) on the twisted intramolecular charge transfer (TICT) of ρ-N, N-dimethylaminobenzaldehyde (DMABA) are investigated using fluorescence spectroscopy. The typical TICT dual fluorescence of DMABA is observed in pure water and aqueous β-CD solution, and β-CD has s remarkable influence on the TICT fluorescence characteristics of DMABA. A linear dependence of the ratio of intensity of TICT fluorescence band (a band) to that of normal fluorescence band (b band) on DMABA concentration is also observed and the introduction of β-CD increases the linear slope. Combined with the results of absorption spectroscopy, fluorescence polarization, and peculiar salt effects, the properties of TICT state of DMABA, the interaction of DMABA with β-CD, and the intrinsic traits of the microenvironmental effects of β-CD are discussed in detail.展开更多
基金Project supported by the National Natural Science Foundation of Chinathe Natural Science Foundation of Fujian Province
文摘Twisted intramolecular charge transfer (TICT) is one of the hot points in condensed phase photochemistry at the present time. Most of the studies on TICT up to now, however, are performed in organic medium, which leads to a correlation that the intensity ratio of the long-wavelength TICT fluorescence band (a band) to shortwavelength normal fluorescence band (b band), I_a/I_h, increases with the medium polarity. It is unknown whether such a correlation is applicable to aqueous solution or it is in the transition from organic solvent through water. Thus a systematic study of TICT in aqueous solution and its comparison with that in organic medium are significant for the development and deepening of the theory and application of TICT. In the present note, a steady-state fluorescence spectroscopic study of TICT of p-N, N-dimethylaminobenzoic acid (DMABOA) in aqueous cetyltrimethylammonium chloride (CTMAC) micellar solution is described.
文摘Synchronous fluorometry can cause a band-narrowing effect to improving the fluorometric selectivity (Fig. 1). However, since the △λ value selected is usually small (generally about 0—5 nm) in synchronous scanning, the interference of solvents scattering light (mainly Rayleigh scattering light) is so serious that the sensitivity and the detection limit are harmed greatly.
基金Project supported by the Natural Science Foundation of Fujian Province, China.
文摘The microenvironmental effects of β-cyclodextrin (β-CD) on the twisted intramolecular charge transfer (TICT) of ρ-N, N-dimethylaminobenzaldehyde (DMABA) are investigated using fluorescence spectroscopy. The typical TICT dual fluorescence of DMABA is observed in pure water and aqueous β-CD solution, and β-CD has s remarkable influence on the TICT fluorescence characteristics of DMABA. A linear dependence of the ratio of intensity of TICT fluorescence band (a band) to that of normal fluorescence band (b band) on DMABA concentration is also observed and the introduction of β-CD increases the linear slope. Combined with the results of absorption spectroscopy, fluorescence polarization, and peculiar salt effects, the properties of TICT state of DMABA, the interaction of DMABA with β-CD, and the intrinsic traits of the microenvironmental effects of β-CD are discussed in detail.
