Reactivity of azides in the solid state. I. Optical properties and photochemical decomposition of thallous azide

1960 ◽  
Vol 256 (1287) ◽  
pp. 514-527 ◽  
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Electron Energy ◽  
Energy Levels ◽  
Wavelength Region ◽  
Mercury Lamp ◽  
Silver Azide ◽  
Photochemical Decomposition ◽  
Angle Method ◽  
Narrow Bands

The photochemical decomposition of the ionic thallous azide to metallic thallium and nitrogen has been studied as a function of wavelength, temperature and light intensity. Two values have been obtained for the activation energies; 0⋅33 eV corresponding to the full output of a mercury lamp, and 0⋅14 eV for light in the wavelength region 3200 to 3800 Å. The quantum efficiency at 3650 Å is 2×10 -3 . Two exciton bands at 3415 and 3348 Å have been observed in thallous azide by the method of low-temperature spectroscopy developed by Nikitine and Gross. Two narrow bands have been resolved in silver azide which is also an ionic azide, in the region previously studied by McLaren & Rogers. These bands occur at 3608 and 3590 Å. The refractive index of thallous azide has been measured by the Brewster angle method, and the electron energy levels have been estimated. The results of the photochemical decomposition of thallous azide have been related to the electron energy levels, and to measurements of photoconductivity made by Evans & Yoffe.

scholarly journals Studying the Nonlinear Optical Properties of Fluoride Laser Host Materials in the Ultraviolet Wavelength Region

2021 ◽  
Vol 12 (1) ◽  
pp. 372
Author(s):  
Duong Van Pham ◽  
Diep Van Nguyen ◽  
Tu Xuan Nguyen ◽  
Kieu Anh Thi Doan ◽  
Quan Minh Le ◽  
...  
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Ultrashort Pulse ◽  
Nonlinear Refractive Index ◽  
Nonlinear Optical ◽  
Wavelength Region ◽  
Aluminum Fluoride ◽  
Self Focusing ◽  
Host Materials ◽  
Ultraviolet Wavelength

Fluoride host materials doped with trivalent cerium ions have previously been demonstrated as successful laser materials in the ultraviolet wavelength region. However, the nonlinear optical properties of the fluoride hosts in this wavelength region have not been investigated yet, although nonlinearity could result in undesirable effects such as self-focusing and pulse distortion when these fluoride materials are used as gain media in high-power, ultrashort pulse laser oscillator and amplifier systems. In this work, the nonlinear refractive index of lithium calcium aluminum fluoride (LiCaAlF6), lithium strontium aluminum fluoride (LiSrAlF6), lanthanum fluoride (LaF3), and yttrium lithium fluoride (YLiF4) fluoride host materials are determined using the Kramers–Krönig relation model in the ultraviolet wavelength region. Self-focusing conditions, particularly at the peak laser emission wavelength of these materials, are further analyzed. Results show that LiCaAlF6 has the smallest nonlinear refractive index and self-focusing, making it an ideal host material under the conditions of ultrashort pulse and ultrahigh-power laser generation.

Optical Properties of Erbium Doped Tellurite Glasses

2016 ◽  
Vol 864 ◽  
pp. 37-41 ◽  
Author(s):  
Mukhayyarotin Niswati Rodliyatul Jauhariyah ◽  
Cari ◽  
Ahmad Marzuki
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Room Temperature ◽  
Optical Band Gap ◽  
Band Gap Energy ◽  
Tellurite Glasses ◽  
Ion Content ◽  
Gap Energy ◽  
Erbium Doped ◽  
Angle Method

This paper presents the optical properties of erbium doped tellurite glasses with the composition of 55TeO2-2Bi2O3-35ZnO-5PbO-(3-x)Na2O-xEr2O3 where x = 0, 0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 mol% . Refractive index of the glasses was measured using Brewster’s angle method and their optical absorption spectra were measured in spectral range 200 – 1100 nm recorded at room temperature. The results show that the glass refractive index increases with the increase of Er3+ ion content in the glass and the optical band gap energy decreases with the increase of erbium content in the glass.

Electron–phonon interaction influence on optical properties of parallelogram quantum wires

2014 ◽  
Vol 28 (22) ◽  
pp. 1450142 ◽  
Author(s):  
H. Bahramiyan ◽  
R. Khordad ◽  
H. Azari
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Quantum Wire ◽  
Quantum Wires ◽  
Energy Levels ◽  
Moment Matrix ◽  
Absorption Coefficients ◽  
Phonon Interaction ◽  
Electron Phonon Interaction ◽  
Index Changes

In the present work, we have studied the effect of electron–phonon (e–p) interaction on optical properties of a GaAs quantum wire with parallelogram cross-section. For this goal, we have calculated refractive index changes and absorption coefficients by using compact-density-matrix approach and iterative method. The results show that the refractive index changes and absorption coefficients are obviously increased and the peak positions shift toward higher energies after considering the e–p interaction. We have also studied polaronic effect on electric dipole moment matrix elements and the energy levels for different quantum wire sizes. We have found that the line-width of absorption coefficients and refractive index changes is approximately constant after considering e–p interaction.

Optical properties of polycrystalline CdSe films

1992 ◽  
Vol 7 (5) ◽  
pp. 1243-1246 ◽  
Author(s):  
Tapan K. Gupta ◽  
Jim Doh
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Absorption Coefficient ◽  
Electroless Deposition ◽  
Wavelength Region ◽  
Strong Absorption ◽  
Uv Reflectance ◽  
Reflectance Measurements ◽  
Deposition Techniques

The optical properties of polycrystalline CdSe films prepared using electroless deposition techniques are discussed. Refractive index measurements are reported for the wavelength region 400–2000 nm. Extinction and absorption coefficient measurements are reported for the strong absorption regime (450–750 nm). UV reflectance measurements are also discussed.

scholarly journals Study of Absorption Spectra, Fluorescence and Energy Levels of Fluorescein Dye

2018 ◽  
Vol 26 (8) ◽  
pp. 164-175
Author(s):  
Afrah M. AL Hussainey ◽  
Salar Hussein Ibrahem ◽  
Talib M. Abbas ALShafie
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Infrared Spectroscopy ◽  
Absorption Coefficient ◽  
Liquid State ◽  
Energy Levels ◽  
Laser Medium ◽  
Linear Absorption ◽  
Fluorescein Solution ◽  
Fluorescein Dye

The absorption and fluorine spectra of dissolved fluorescein solution in ethanol and different concentrations were studied. The optical properties(absorbance, permeability, linear absorption, and refractive index, as well as time and fluoridation)were calculated. The results showed that a decrease in concentration leads to a decrease in absorption values and an increase in permeability values. This results in a decrease in the values of the absorption coefficient and refractive index. This is in accordance with Lambert's law. Also, the values of the fluorine are lower. The top of the emission spectrum is transferred to the longer wavelengths. The temporal age of fluoride decreases and the quantitative output increases, thus using this dye as an effective laser medium in liquid state lasers. The infrared spectroscopy of the dye was also studied using the (Gaussian 9) program.                                         

Optical and Physical Properties of Cu-Co Doped in Soda Lime Silicate Glasses

2017 ◽  
Vol 728 ◽  
pp. 143-148
Author(s):  
Nattapon Srisittipokakun ◽  
Jakrapong Kaewkhao
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Absorption Spectrum ◽  
Optical Absorption ◽  
Room Temperature ◽  
Wavelength Region ◽  
Soda Lime ◽  
Silicate Glasses ◽  
Melt Quenching ◽  
Co Doped

Co/Cr co-doped in soda lime silicate (SLS) glasses were prepared by using normal melt quenching technique. The current composition was prepared based on the proposed ratio: (64.9-x)SiO2: 10CaO: 25Na2O: 0.1CuO: xCoO where x=0.00, 0.01, 0.02, 0.03, 0.04 and 0.05 mol% were prepared at 1200°C for 3 h, and annealed at 500 °C for 3 h. The physical and optical properties of Co/Cr co-doped in SLS glasses were investigated such as density, molar volume, refractive index and optical absorption were discussed and measured. The optical absorption spectrum of Co/Cr co-doped in SLS glasses measured at room temperature in the wavelength region 200–1100 nm were presented.

Structure and stability of inorganic azides. II. Some physical and optical properties, and the fast decomposition of solid monovalent inorganic azides

1959 ◽  
Vol 250 (1262) ◽  
pp. 346-366 ◽  
Keyword(s):  
Energy Levels ◽  
Metal Particles ◽  
Refractive Indices ◽  
Melting Points ◽  
Silver Azide ◽  
Self Heating ◽  
Photochemical Decomposition ◽  
Molten Phase ◽  
The Stability ◽  
Fast Decomposition

The stability (isothermal decomposition) to heat and light of a series of monovalent inorganic azides is considered. The stability decreases in the order KN 3 , TIN 3 , AgN 3 and CuN 3 . This is the order of increasing ionization potential of the metal. Measurements have been made on a number of the physical properties of these compounds, such as the refractive indices, ab­sorption spectra, photoconductivity, and melting points. The electron energy levels of these solids has also been estimated. These include the energy (optical and thermal) required to form an exciton and where appropriate the energy required to dissociate the exciton to give an electron in the conduction band. The relation of these measurements to the decomposition mechanism is considered. The critical light energy required to ignite a pellet of silver azide is reduced by the addition of colloidal gold (or silver). The metal particles are thought to act as electron traps during the initial photochemical decomposition. This increases the extent of the decomposition. The growth of the explosion, however, is a thermal process in which there is self heating of the azide and an accelerated rate of decomposition. A molten phase is probably necessary for the fast decomposition of the inorganic azides.

Modification of optical properties of PC-PBT/Cr2O3 and PC-PBT/CdS nanocomposites by gamma irradiation

2020 ◽  
Vol 92 (2) ◽  
pp. 20402
Author(s):  
Kaoutar Benthami ◽  
Mai ME. Barakat ◽  
Samir A. Nouh
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Band Gap ◽  
Color Difference ◽  
Band Gap Energy ◽  
Polybutylene Terephthalate ◽  
Γ Irradiation ◽  
Gap Energy ◽  
Vis Spectroscopy ◽  
Oxygen Atoms

Nanocomposite (NCP) films of polycarbonate-polybutylene terephthalate (PC-PBT) blend as a host material to Cr2O3 and CdS nanoparticles (NPs) were fabricated by both thermolysis and casting techniques. Samples from the PC-PBT/Cr2O3 and PC-PBT/CdS NCPs were irradiated using different doses (20–110 kGy) of γ radiation. The induced modifications in the optical properties of the γ irradiated NCPs have been studied as a function of γ dose using UV Vis spectroscopy and CIE color difference method. Optical dielectric loss and Tauc's model were used to estimate the optical band gaps of the NCP films and to identify the types of electronic transition. The value of optical band gap energy of PC-PBT/Cr2O3 NCP was reduced from 3.23 to 3.06 upon γ irradiation up to 110 kGy, while it decreased from 4.26 to 4.14 eV for PC-PBT/CdS NCP, indicating the growth of disordered phase in both NCPs. This was accompanied by a rise in the refractive index for both the PC-PBT/Cr2O3 and PC-PBT/CdS NCP films, leading to an enhancement in their isotropic nature. The Cr2O3 NPs were found to be more effective in changing the band gap energy and refractive index due to the presence of excess oxygen atoms that help with the oxygen atoms of the carbonyl group in increasing the chance of covalent bonds formation between the NPs and the PC-PBT blend. Moreover, the color intensity, ΔE has been computed; results show that both the two synthesized NCPs have a response to color alteration by γ irradiation, but the PC-PBT/Cr2O3 has a more response since the values of ΔE achieved a significant color difference >5 which is an acceptable match in commercial reproduction on printing presses. According to the resulting enhancement in the optical characteristics of the developed NCPs, they can be a suitable candidate as activate materials in optoelectronic devices, or shielding sheets for solar cells.

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