Concentration Effects on the Fluorescence of PBD and Butyl-PBD

Horrocks, Donald L.

doi:10.1063/1.1712347

Cited by 13 publications

(2 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In fact, the red-shifted and extremely broad and structureless profile of the emission band supports such a conclusion. Indeed, oxazoles are known to exhibit weak excimeric emission 26 and have been reported for several oxazoles, although excimer formation is unfavorable as demonstrated by the theoretical calculations of Lami 26c-d Dissolution of the LB films in ethanol reproduced the intense fluorescence emission spectrum, confirming that the observed effects did not arise from impurities or artifacts.…”

Section: Resultssupporting

confidence: 66%

Spectroscopic Study of Nonamphiphilic 2,2‘-p-Phenylenebis(5-phenyloxazol) (POPOP) Assembled in Supramolecular Langmuir−Blodgett Films

Dutta

1997

J. Phys. Chem. B

View full text Add to dashboard Cite

This paper reports the incorporation of a nonamphiphilic blue laser dye 2,2′-p-phenylenebis(5-phenyloxazol), abbreviated as POPOP, in Langmuir-Blodgett (LB) films mixed with stearic acid (SA) and their spectroscopic properties. The surface pressure versus area per molecule isotherms of POPOP mixed with SA at different molar ratios reveal a plateau-like region that suggests reorientation of the POPOP molecules from lying flat at the air-water interface to an almost vertical alignment. Miscibility studies indicate a repulsive type of interaction between the components in the mixture, resulting in the formation of microcrystallites in the LB films that is confirmed by spectroscopic studies. Perhaps the most interesting feature of this study is the appearance of a new band at about 400 nm in absorption spectra of the mixed LB film of POPOP and SA that is assigned to a low-lying hidden 1 L b state. The appearance of the same band in a mixture of ethanol and water with the volume fraction of water in the mixture exceeding 76% confirms that the manifestation of this band is aggregation induced. Fluorescence emission studies of POPOP in solution reveal a structured emission that originates from the 1 L a state, while the emission studies from the LB films exhibit two bands, one at 420 nm originating from the low-lying 1 L b state of the monomer and the other at 460 nm corresponding to a 1 L b dimer. Excitation and polarized anisotropy measurements confirm these findings and indicate that the above observations may be attributed to a deformed geometry of the POPOP molecules in the LB films.

show abstract

Section: Resultssupporting

confidence: 66%

Spectroscopic Study of Nonamphiphilic 2,2‘-p-Phenylenebis(5-phenyloxazol) (POPOP) Assembled in Supramolecular Langmuir−Blodgett Films

Dutta

1997

J. Phys. Chem. B

View full text Add to dashboard Cite

show abstract

“…The intense emission in the 420 -430 nm range has previously been attributed to self-reabsorption of the short wavelength uorescence. 21 In a later study, Horrocks 22 interpreted this intense long-wavelength as excimer uorescence. Agbaria et al 8,9 used the latter interpretation to assign the excimer/dimer emission wavelength of PPO:g-CD aggregates around 420 nm .…”

Section: Resultsmentioning

confidence: 96%

Spectroscopic Studies of Cyclodextrin Complexes with 2,5-Bis-(4-Methylphenyl)Oxazole

Yarabe¹,

Agbaria²,

Rugutt³

et al. 2002

Appl Spectrosc

View full text Add to dashboard Cite

The complexation of γ-cyclodextrins (γ-CDs) with the guest molecule 2,5-bis-(4-methylphenyl)oxazole (MPPO) has been studied by use of fluorescence spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and dynamic light scattering (DLS). The changes in the 1H NMR aromatic signals of MPPO in aqueous γ-CD provide evidence of complexation and inclusion. DLS was used to confirm the existence of a distribution of the aggregates in the nanometer range. Excimer fluorescence was pronounced in the presence of γ-CD. The evidence of the existence of two species was shown through fluorescence lifetime data. The emission intensities of the steady state fluorescence and the fluorescence anisotropies of the linear aggregates revealed a phase transition temperature of 60 °C.

show abstract

Developments of macromolecular scintillators—I. Synthesis and characterization of copolymers of vinyl-t-butyl PBD

Anderson

Davidson

Soutar

1989

European Polymer Journal

View full text Add to dashboard Cite

Concentration Effects on the Fluorescence of PBD and Butyl-PBD

Cited by 13 publications

References 7 publications

Spectroscopic Study of Nonamphiphilic 2,2‘-p-Phenylenebis(5-phenyloxazol) (POPOP) Assembled in Supramolecular Langmuir−Blodgett Films

Spectroscopic Study of Nonamphiphilic 2,2‘-p-Phenylenebis(5-phenyloxazol) (POPOP) Assembled in Supramolecular Langmuir−Blodgett Films

Spectroscopic Studies of Cyclodextrin Complexes with 2,5-Bis-(4-Methylphenyl)Oxazole

Developments of macromolecular scintillators—I. Synthesis and characterization of copolymers of vinyl-t-butyl PBD

Contact Info

Product

Resources

About