Study of the absorption spectra of the 4f electron transition of the Nd and Er complexes with 2-isobutylformyl-1,3-dione-indane in the presence of TX-100 and its analytical application

Abstract The complex quantum-chemical and spectral study of the anionic polymethine dyes with the simplest symmetrical terminal groups and with different length polymethine chain is performed. It was shown that these dyes produce the specific molecular orbitals positioned nearly the energy gap and located only within the terminal groups. By investigation of the absorption spectra, it was established that the typical highly intensive longwawelength spectral band is observed which are bathochromically shifted upon lengthening of the open conjugated chain; this polymethine band is connected with the electron transition between the frontier levels of the opposite symmetry. In the contrast, the local MOs take part in so-called quasi-local electron transitions involved also one the frontier orbital. The local transitions have small dipole moments and hence they do practically not appear in the absorption spectra, however, the local transitions cause the appearance of the non-deep minima in the spectra of the fluorescence excitation anisotropy.

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STRUCTURES AND SPECTROSCOPIC PROPERTIES OF THREE AROMATIC HETEROCYCLIC DYE PHOTOSENSITIZERS

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633613500557 ◽

2013 ◽

Vol 12 (06) ◽

pp. 1350055

Author(s):

YUANZUO LI ◽

CHAOFAN SUN ◽

LINPO YANG

Keyword(s):

Density Functional Theory ◽

Absorption Spectra ◽

Density Functional ◽

Energy Levels ◽

Electron Transition ◽

Spectroscopic Properties ◽

Molecular Orbitals ◽

Functional Theory ◽

Solvent Phase ◽

Charge Difference Density

The ground-state structures and absorption spectra of three dyes, carbazole, phenothiazine and diphenylamine, were studied by the density functional theory (DFT) and time-dependent density functional theory (TD-DFT). The strong absorption peak, electron transition as well as the energy levels of molecular orbitals were obtained and compared in the gas and solvent phase. Furthermore, we further calculated the effect of the expanding conjugated bridge on the absorption spectra and the energy levels of molecular orbitals. Visualized method of charge difference density (CDD) was used to show the direction of charge transfer in the molecules of interest during photo-excitation.

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Absorption Spectra of 4f Electron Transitions of Neodymium and Erbium with 8-Hydroxyquinoline-5-sulphonic Acid and Diethylamine Systems and Its Analytical Application

Analytical Letters ◽

10.1080/00032719208020064 ◽

1992 ◽

Vol 25 (6) ◽

pp. 1119-1130 ◽

Cited By ~ 1

Author(s):

Wang Naixing ◽

Qi Ping

Keyword(s):

Absorption Spectra ◽

Sulphonic Acid ◽

Analytical Application ◽

Electron Transitions

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Single-Photon-Single-Electron Transition for Interpretation of Optical Spectra of Nonspherical Metal Nanoparticles in Aqueous Colloidal Solutions

Journal of Nanomaterials ◽

10.1155/2018/1781389 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8

Author(s):

J. Michael Köhler ◽

Danja Kuhfuß ◽

Phillip Witthöft ◽

Martina Hentschel ◽

Andrea Knauer

Keyword(s):

Metal Nanoparticles ◽

Absorption Spectra ◽

Noble Metal ◽

Single Photon ◽

Electron Transition ◽

Optical Spectra ◽

Single Electron ◽

Noble Metal Nanoparticles ◽

Analytic Description ◽

Anisotropic Particles

Noble metal nanoparticles—especially shape anisotropic particles—have pronounced resonances in the optical spectrum. These sensitive absorption modes attract great interest in various fields of application. For nonspherical particles, no analytic description of the absorption spectra according to the commonly used Mie theory is possible. In this work, we present a semi-empirical approach for the explanation of the optical spectra of shape anisotropic particles such as silver nanoprisms and gold nanorods. We found an interpretation of the optical absorption spectra which is based on a single-photon-single-electron transition. This model is in a better agreement with the basic assumptions of quantum mechanics than the electrodynamic model of a localized surface plasmon excitation. Based on microfluidically obtained Ag nanoprisms and Au nanorods with very high ensemble homogeneities, dependencies between the geometrical properties of the shape anisotropic noble metal nanoparticles and the spectral position of the longitudinal absorption mode could be derived, which show that the assumption of a composed relative permittivity and the inclusion of the Rydberg constant is sufficient to describe the optical properties of the shape anisotropic particles. Within the scope of the measuring accuracy, the calculations furthermore lead to the value of the refractive index of the particle-surrounding medium.

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