Polarized absorption and emission spectra of stilbazolium merocyanines

Fra̧ckowiak, D.; Gruda, Ilona; Niedbalska, M.; Romanowski, Marek; Dudkowiak, Alina

doi:10.1016/1010-6030(90)87006-w

Cited by 24 publications

(18 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example for mero-E in k15 the maximum at 636 nm s = 0.165 and for the same dye for the maximum at 589 nm s = 0.151 whereas for the protonated form it equals s = -0.0133. The orientation factors of both maxima belonging to the free base form of dye are similar which supports our previous conclusion [8] that these maxima represent two vibronic transitions of the same form. The angles (β) between the direction of the transition moments of absorption and the direction of the preferential orientation axis calculated from the formula s = (3 cost β -1)/2 are also similar for both free base forms whereas for the protonated form is strongly different ( Table I).…”

Section: Resultssupporting

confidence: 89%

“…In MBBA + EBBA the dyes are in a much higher degree protonated as it follows from Fig. 2c and from the previous results [4,8,9].…”

Section: Methodssupporting

confidence: 81%

“…On the basis of 1(V) dependences the capacities and resistances of the cell according to the method given in Ref. [8] were calculated and gathered in Table II. As it follows from this table the resistances of the cells are decreasing and capacities are increasing as a result of the cell illumination.…”

Section: Resultsmentioning

confidence: 99%

See 2 more Smart Citations

Photoelectrochemical Cell with Dye Molecules Oriented in Nematic Liquid Crystal

1997

View full text Add to dashboard Cite

A photoelectrochemical cell consisting of two semiconducting electrodes covered by orienting SiO x layers and filled with merocyanine solutions in nematic liquid crystal was constructed. Dye molecules were oriented as a result of the guest-host effect. Generation of photocurrent by two components of polarized light gives different values of photocurrent"ampalitude but anisotropy of photocurrent is lower than that of absorption in the region of a free base form of dye. It is explained by dominant participation of a protonated form of dye in the photocurrent generation. The 1ast form exhibits a lower degree of orientation than the free base form of dye.

show abstract

Section: Resultssupporting

confidence: 89%

“…In MBBA + EBBA the dyes are in a much higher degree protonated as it follows from Fig. 2c and from the previous results [4,8,9].…”

Section: Methodssupporting

confidence: 81%

See 1 more Smart Citation

Photoelectrochemical Cell with Dye Molecules Oriented in Nematic Liquid Crystal

1997

View full text Add to dashboard Cite

show abstract

“…In the present paper, we wish to check if the SPCE effect occurs for the stilbazolium merocyanine shown in Figure 1. For the dye being investigated, the situation is complex because stilbazolium merocyanine dyes in some samples occur in two species: protonated absorbing at 390 nm and also in free-base form absorbing at 559 nm and emitting in longer wavelength region, created usually by solvatochromic effects [5,18] or by interactions with ions [6,16,17]. As follows from the investigation of stilbazolium merocyanines in anisotropic media, such as stretched polymer [4,19,20] or in liquid crystal [7], for such dyes located in the oriented systems, two polarized components of absorption and emission are very often different.…”

Section: Introductionmentioning

confidence: 99%

“…As follows from the investigation of stilbazolium merocyanines in anisotropic media, such as stretched polymer [4,19,20] or in liquid crystal [7], for such dyes located in the oriented systems, two polarized components of absorption and emission are very often different. Biological systems are in most cases anisotropic; therefore, the spectra observed for a dye located in such a system can depend on exciting or absorbed light polarization [4,18]. The dye molecules gathered in close proximity to a colloidal particle can also be, to some extent, oriented with respect to the colloid surface.…”

Section: Introductionmentioning

confidence: 99%

Influence of Silver Colloid Presence on Stilbazolium Merocyanine Emission

Siejak

Fra̧ckowiak

2007

Plasmonics

View full text Add to dashboard Cite

Absorption, fluorescence emission, and fluorescence excitation spectra of stilbazolium merocyanine (1-(n-butyl)-4[(3,5-dimethoxy-4-oxocyclohexa-2,5-dienylidene) ethylidene]-1,4-dihydropyridyne) dye in water solution without and with colloidal silver addition were measured. In the presence of the colloid, besides the absorption band assigned to the protonated species of the dye (at 391 nm), an absorption band related to the free-base species appears at 490 nm. From the absorption and emission spectra, measured at various dye concentrations, follows that the aggregates are not effectively formed. Therefore, the long-wavelength absorption and fluorescence bands have to be related to some dye forms created by the solvatochromic effects. The fluorescence bands of the protonated and the free-base species are located at 559 nm and at about 630 nm, respectively. The shape of the long-wavelength band suggests the occurrence of more than one free-base form of the dye. At some dye and colloid concentrations, the global emission of the sample is enhanced as a result of silver addition. The increase in the emission yield of the dye could be partially due to not only the change in the concentrations of dye forms exhibiting various emission yields but is also due to the resonance surface plasmon effect. Because of the superposition of several effects, before the practical application of merocyanine as an indicator of metal presence in biological samples, its spectral properties in the system investigated should be established.

show abstract

Stilbazolium merocyanine dye determination in different solutions, concentrations and colloids using SERS

Pajchrowski¹,

Abdali²,

Nørbygaard³

2006

J Raman Spectroscopy

View full text Add to dashboard Cite

Surface-enhanced Raman scattering (SERS) measurements were carried out on stilbazolium merocyanine dye in methanol and pyridine solvents. Both solutions were measured in a series of concentrations covering a range of 5 × 10 −5 M to 5 × 10 −8 M. In these measurements, Ag and Au colloids were used, and the results have shown that Ag colloids yield better enhancement in the Raman spectra of this dye. Moreover, the effect of adding NaCl solution to the SERS samples was also studied. All measurements were carried out using the state-of-the-art ChiralRaman instrument, which utilizes a 532 nm laser source. We report here on the success of using SERS to obtain Raman spectra of merocyanine dye at very low concentrations in an attempt to find a new approach that can be used for further investigations of the dye. The SERS spectra are reported here, and the results from different solutions, colloids, concentrations and pH values are compared.

show abstract

Polarized absorption and emission spectra of stilbazolium merocyanines

Cited by 24 publications

References 13 publications

Photoelectrochemical Cell with Dye Molecules Oriented in Nematic Liquid Crystal

Photoelectrochemical Cell with Dye Molecules Oriented in Nematic Liquid Crystal

Influence of Silver Colloid Presence on Stilbazolium Merocyanine Emission

Stilbazolium merocyanine dye determination in different solutions, concentrations and colloids using SERS

Contact Info

Product

Resources

About