Temperature behavior of optical absorption bands in colored LiF crystals

Zeeman spectroscopy is not practicable for the investigation of the structure of electronic conventional states which give rise to broad optical absorption bands in solids. We have investigated the application of Faraday rotation and circular dichroism techniques to absorption bands of neutral silver atoms and F centres in alkali halides. These centres give rise to optical absorption bands due to transitions of the type 2 S → 2 P which are 2000 to 6000 cm -1 in width because, in part, of strong coupling to lattice phonons. A discussion is given of information which may be obtained concerning the electonic states involved in the 2 S → 2 P transition by analysis of the magneto-optical effects by the method of moments. It is shown, for example, that the spin-orbit coupling constant of the 2 P state of the silver atom is reduced from 613 cm -1 in the free state to 365 cm -1 in KCl, to 102 cm -1 in KBr and to an unmeasurably small value in KI. This cancellation of spin-orbit interaction of the silver atom is assigned to symmetry allowed admixtures of lattice ion wavefunctions into the 2 P state.

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Optical Absorption and Photoluminescence Properties of Dy3+ Ions in Bi2O3-SiO2-B2O3 Glass System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.979.280 ◽

2014 ◽

Vol 979 ◽

pp. 280-284

Author(s):

Narong Sangwaranatee ◽

Yaowaluk Tariwong ◽

Sunisa Sarachai ◽

Jakrapong Kaewkhao ◽

Natthakridta Chanthima

Keyword(s):

Optical Absorption ◽

Emission Spectrum ◽

Molar Volume ◽

Borosilicate Glass ◽

Excitation Wavelength ◽

Optical Absorption Spectra ◽

Photoluminescence Spectra ◽

Photoluminescence Properties ◽

Melt Quenching ◽

Absorption Bands

This research studied the effect of dysprosium on the physical, optical and luminescence properties of the bismuth borosilicate glass in compositions 40Bi2O3 : 20SiO2 : (40-x)B2O3 : xDy2O3 (where x = 0.0, 0.5, 1.0, 1.5, 2.0 and 2.5 mol%). The glass systems have been prepared at 1100 °C by melt quenching technique. The results showed that the density and molar volume of glass samples are between 4.6477 ± 0.0020 to 5.0047 ± 0.0041 g/cm3 and 45.6608 to 48.6797 cm3/mol, respectively. The values of density and molar volume of these glasses were not depend on the Dy2O3 concentration. The optical absorption spectra of glass samples in the UV-Vis-NIR region shows absorption bands at 794, 906, 1094, 1276 and 1690 nm, respectively. The photoluminescence spectra show emission bands at 482 (blue), 576 (green), 663 (yellow) and 756 (red) nm under 453 nm excitation wavelength. The emission spectrum at 576 nm has shown a strongest intensity.

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Excitonic Bands in the Optical Absorption Spectra of A3MX6 and A3M2X9 (A = MeNH3, Me2NH2, Me3NH, Me4N; M = Bi, Sb; X = Cl, Br, I)

Zeitschrift für Naturforschung B ◽

10.1515/znb-1994-0620 ◽

1994 ◽

Vol 49 (6) ◽

pp. 849-851 ◽

Cited By ~ 6

Author(s):

G. C. Papavassiliou ◽

I. B. Koutselas

Keyword(s):

Optical Absorption ◽

Absorption Spectra ◽

Spectral Region ◽

Visible Spectral Region ◽

Optical Absorption Spectra ◽

Absorption Bands ◽

Uv Visible ◽

Low Dimensional

The title compounds (natural low-dimensional semiconductors) show strong excitonic optical absorption bands in the UV-visible spectral region, because of the dielectric confinement of excitons. as in the cases of other similar systems based on PbX2-4, SnX2-4. PtI - X - PtIV-X , Cdx,Sy-clusters etc

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Optical absorption of LiNaGe4O9:Mn crystal

Journal of Physics and Electronics ◽

10.15421/332110 ◽

2021 ◽

Vol 29 (1) ◽

pp. 69-72

Author(s):

A. Yu. Osetsky ◽

T. V. Panchenko ◽

M. D. Volnianskii ◽

M. P. Trubitsyn

Keyword(s):

Field Theory ◽

Optical Absorption ◽

Ferroelectric Phase Transition ◽

Ferroelectric Phase ◽

Optical Absorption Spectra ◽

Crystal Field Theory ◽

Absorption Bands ◽

Additional Absorption ◽

Impurity Ions ◽

Semi Empirical

The paper reports the results of optical absorption spectra studying in LiNaGe4O9 crystal doped with Mn. It is shown that Mn impurity causes the appearance of the additional absorption bands. The intensities of these bands change in different ways in the range of the ferroelectric phase transition. Semi-empirical version of the crystal field theory is used to discuss localization and charge state of Mn impurity ions in the LiNaGe4O9 structure.

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Characterization of Nanoclusters in MgO Created by Means of Ion Implantation.

MRS Proceedings ◽

10.1557/proc-792-r8.10 ◽

2003 ◽

Vol 792 ◽

Author(s):

M.A. van Huis ◽

A. van Veen ◽

H. Schut ◽

B.J. Kooi ◽

J.Th.M. De Hosson

Keyword(s):

Optical Absorption ◽

Ion Implantation ◽

Noble Gas ◽

Optical Absorption Spectroscopy ◽

Metal Nanoclusters ◽

Absorption Bands ◽

Cross Sectional ◽

Salt Structure ◽

Scherrer Formula ◽

Gas Clusters

ABSTRACTMetal nanoclusters (NCs) of lithium, zinc, silver and gold embedded in MgO were created by means of ion implantation of Li, Zn, Ag and Au ions into single crystals of MgO(100) and subsequent thermal annealing. Nanoclusters of the compound semiconductor CdSe were obtained by implantation of both Cd and Se ions. Solid noble gas clusters were formed by Kr ion implantation. Optical and structural properties of the NCs were investigated using optical absorption spectroscopy (OAS), high-resolution X-ray diffraction (XRD) and cross-sectional transmission electron microscopy (XTEM). The mean nanocluster size is estimated from the broadening of the Mie plasmon optical absorption bands using the Doyle formula. These results are compared with the NC size as obtained from XRD (using the Scherrer formula) and from direct XTEM observations. The three methods are found to be in reasonable agreement with a mean size of 4.0 and 10 nm found for the Au and Ag clusters, respectively. Using TEM observations, the relative interface energies of MgO//Au and MgO//Ag interfaces are also determined. In the case of MgO//Au, they are found not to be in agreement with theoretical predictions in the literature. CdSe nanoclusters were found to adopt different crystal structures dependent on the size. Small ones (<5 nm) appear to have a rock salt structure, larger ones the sphalerite structure. The solid krypton NC's are under high pressure. The pressure of individual Krypton bubbles was determined from the moiré fringes

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