scispace - formally typeset
Search or ask a question
Topic

Excimer

About: Excimer is a research topic. Over the lifetime, 3725 publications have been published within this topic receiving 75104 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: In this paper, fluorescence spectra and fluorescence decay times of naphthalene and methylnaphthalenes in solution have been measured under various conditions, i.e. in several different solvents and at different temperatures from 300°k to 100°k.
Abstract: Fluorescence spectra and fluorescence decay times of naphthalene and methylnaphthalenes in solution have been measured under various conditions, i.e. in several different solvents and at different temperatures from 300°k to 100°k. Furthermore, the concentration dependence of the fluorescence decay time was examined in detail in order to determine the fluorescence lifetime of the excimer. The mechanism of the excimer formation and decomposition reaction is discussed on the basis of observed results.

47 citations

Journal ArticleDOI
TL;DR: The semi-empirical theory of excimer luminescence in the Pariser-Parr-Pople scheme is shown to be formally equivalent to, but much simpler than, the theories based on the molecular exciton-charge resonance concept as discussed by the authors.
Abstract: The semiempirical theory of excimer luminescence in the Pariser–Parr–Pople scheme [Paper I, J. Chem. Phys. 48, 2589 (1968)] is shown to be formally equivalent to, but much simpler than, the theories based on the molecular exciton–charge resonance concept. On the basis of an assumption that excimers possess D2h equilibrium conformation, the question of the stability of the excimer triplet state and the thermal distortion of the excimer as the possible source of dipole‐allowed character of excimer fluorescence is examined. It is shown that excimer triplet states of many polycyclic hydrocarbons are very likely unstable with respect to dissociation into monomer triplet and monomer ground state, and that thermal excitation of torsional distortion can account for the observed radiative lifetime of excimer fluorescence in naphthalene.

47 citations

Journal ArticleDOI
TL;DR: A new pyrene pyridine conjugate (PPC) has been developed as a selective fluorescent sensor for Ag+ ion that exhibits high selectivity and sensitivity toward Ag+ as fluorescence ‘on–off’ behaviour in HEPES-buffered DMSO–H2O solution.
Abstract: A new pyrene pyridine conjugate (PPC) has been developed as a selective fluorescent sensor for Ag+ ion. Probe PPC exhibits high selectivity and sensitivity toward Ag+ as fluorescence ‘on–off’ behaviour in HEPES-buffered DMSO–H2O (1 : 1, (v/v) HEPES = 50 mM, pH = 7.4) solution with a detection limit of 0.29 × 10−8 M−1. The turn-off fluorescence sensing of the Ag+ ion occurs through dual pathways, i.e. changes and alternations in the photophysical properties. The binding of Ag+ ion prevents excimer formation and also induces intramolecular photoinduced electron transfer (PET) from the pyridine–Ag+ ion bound receptor to pyrene because of structural rigidification, which quenches excimer and monomer emissions with a butterfly-like skeleton.

47 citations

Journal ArticleDOI
TL;DR: In this paper, the absorption and polarization spectra from the first excited singlet state of pyrene and the absorption spectrum of the pyrene excimer were obtained by laser flash spectroscopy using a frequency doubled ruby laser pulse of 6 nanoseconds halfwidth.

47 citations

Journal ArticleDOI
TL;DR: In this article, surface modifications on polyethyleneterephthalate (PET) films following excimer UV lamp irradiation induced grafting were studied using contact-angle measurements, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), differential scanning calorimetry (DSC), and Fourier transform infrared spectrography (FTIR).
Abstract: Surface modifications on polyethyleneterephthalate (PET) films following excimer UV lamp irradiation induced grafting were studied. Characteristics of the modifications depending on the conditions during the irradiation were analysed using contact-angle measurements, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). Depending on the conditions during the irradiation different surface modifications were obtained, which can generally be classified regarding the hydrophilic or hydrophobic characteristics of the resulting surface. It is shown that not every substance that meets the general demands will be grafted on synthetic polymers using excimer UV radiation. Examples of agents that can simply be grafted onto polymer surfaces and those that undergo further crosslinking, building up thin films are listed. Agents used for grafting on polymers are 1,5-hexadiene, perfluoro-4-methyl-pent-2-ene, polyethyleneglycol 200, monosilane and polyethylene. The transferability of the effects achieved to substrates such as polyparaphenylene terephthalamide or polymetaphenylene isophthalamide is shown.

47 citations


Network Information
Related Topics (5)
Laser
353.1K papers, 4.3M citations
85% related
Raman spectroscopy
122.6K papers, 2.8M citations
78% related
Excited state
102.2K papers, 2.2M citations
77% related
Polymer
131.4K papers, 2.6M citations
76% related
Aqueous solution
189.5K papers, 3.4M citations
75% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
2023106
2022253
202142
202045
201959
201847