Fluorescence decays and spectral properties of rhodamine B in submono-, mono-, and multilayer systems

Abstract

Absorption and fluorescence properties of rhodamine B in submono-, mono-and multilayer systems adsorbed on fused quartz plates have been studied at 295 and 77 K. Existence of fluorescent and nonfluorescent dimers of rhodamine B at 295 K and a structural change of the aggregate geometry at low temperatures have been postulated. Rates of nonradiative decay and photoinduced electron transfer of dimers adsbrbed on organic crystals and their possible role in hole injection are discussed.

Microviscosity of Supercooled Water Confined within Aminopropyl-modified Mesoporous Silica as Studied by Time-resolved Fluorescence Spectroscopy

“…The biexponential decay profiles are considered to be due to the inhomogeneity of the immobilized RhB, that is, the components of the long and short lifetimes are ascribed to the isolated RhB species and the aggregated RhB species, respectively. 41 The surface density of the RhB molecule is estimated to be 0.3 molecules nm -2 (Table 1), suggesting the possibility of Förster-type energy transfer in the immobilized RhB molecules adjacent to each other. 42 In general, the rate of Förster-type energy transfer is independent of the temperature when the microenvironment around donor and acceptor species is invariant.…”

“…Non-fluorescent H-type aggregates of RhB 41 might be partially formed inside the cylindrical silica pores. On the other hand, the temperature-sensitive long-lifetime component is close to the fluorescence lifetimes for bulk solution systems.…”

Electronic excited states as a probe of surface adsorbate structure and dynamics in liquid xenon

“…(4) each element of SX (2 ) can now be rewritten as (15) In order to evaluate the average, it is necessary to make some assumptions about the molecular distribution function.…”

“…Evaluating the dot products in Eg. (15), inserting the results into Eg. (14), and performing an average of y over the range 0 to 2~ to achieve the desired isotropism about the surface normal, one arrives at a relationship between 6 and ~ for a given R:…”

Highly Sensitive Determination of Dye Molecules on a Surface by the Second Harmonic Generation Technique

“…1 3 Among various optical techniques, the laser-induced fluorescence is famous for its high sensitivity;4 a submonolayer sensitivity on the surface has been established. 5 Similarly, the SHG is a highly sensitive technique for a determination of molecules in the surface layer; this technique is highly surface-specific and allows detection of less than a monolayer of adsorbed molecules, 1,2,6,7 Applications of this technique for determination of surface molecular orientation are popular'-9, but its analytical applications are still rudimentary. Efficiency of the SHG technique becomes higher by using a laser with a higher peak 1 2 But a laser with a large pulse energy may induce photo decomposition of the sample.…”