Shift of emission band upon the excitation at the long wavelength absorption edge. III. Temperature dependence of the shift and correlation with the time dependent spectral shift

1976 ◽  
Vol 65 (7) ◽  
pp. 2550-2555 ◽  
Author(s):  
Tohru Azumi ◽  
Ken‐ichi Itoh ◽  
Hiroshi Shiraishi
Keyword(s):  
Temperature Dependence ◽  
Absorption Edge ◽  
Emission Band ◽  
Spectral Shift ◽  
Time Dependent ◽  
Long Wavelength ◽  
Wavelength Absorption

Die Dispersion des Kerr-Effektes. V.

1969 ◽  
Vol 24 (9) ◽  
pp. 1391-1400 ◽  
Author(s):  
H.G. Kuball ◽  
W. Galler ◽  
R. Göb ◽  
D. Singer
Keyword(s):  
Perturbation Theory ◽  
Absorption Band ◽  
Kerr Effect ◽  
Kerr Constant ◽  
Time Dependent ◽  
Long Wavelength ◽  
Wavelength Absorption ◽  
Definition Of ◽  
Long Wavelength Absorption Band ◽  
Kronig Relation

The definition of a complex Kerr constant follows from the description of the interaction of light with molecules in an electrostatic field. The treatment is based on the time-dependent perturbation theory, assuming a quasi continuum of librational states of the molecules concerned. The Kramers-Kronig relation for the Kerr effect and the electrochromism is deduced from the complex Kerr constant. The results are compared with the measurement of the Kerr effect of one azamerocyanine. For a number of molecules the amplitude of the optical polarizability and of the hyperpolarizability B is calculated for the long wavelength absorption band.

Optical properties of antimony tri-iodide

1963 ◽  
Vol 276 (1364) ◽  
pp. 136-148 ◽  
Keyword(s):  
Single Crystals ◽  
Absorption Edge ◽  
Room Temperature ◽  
Thermal Dissociation ◽  
Optic Axis ◽  
Refractive Indices ◽  
Absorption Bands ◽  
Long Wavelength ◽  
Wavelength Absorption ◽  
Experimental Values

Single crystals of pure antimony tri-iodide in which the optic axis is normal to the crystal plate have been prepared. The ordinary refractive index of antimony tri-iodide has been determined at wavelengths in the absorption edge and out to a wavelength of 2.5 pm. Crystals of the com pound have been shown to be uniaxial negative and the dispersion of the birefringence has been measured. The ordinary and extraordinary refractive indices calculated from the ionic refractivity of iodine agree with the experimental values. Antimony tri-iodide has a long-wavelength absorption edge at about 5000 Å, the variation of absorption coefficient with photon energy being in agreement with Urbach’s equation. Measurements of the light transmitted through an evaporated film 0.1 pm thick at 125 °K have shown that the absorption spectrum consists of a series of absorption bands having absorption coefficients of about 105 cm -1 . These absorption bands have been attributed to two hydrogenlike series of absorption levels, the first members of each series (separation 0.46 eV) being the halogen doublet due to (3/2, 1/2) splitting. The oscillator strength of the first member of the long-wavelength series is 0.65 x 10 -4 per atom at 125 °K. Reflexion measurements from a single crystal at 173 °K have shown that two reflectivity maxima occur in positions corresponding to the absorption bands of the halogen doublet. Photoconductivity has been observed in single crystals at room temperature. The temperature and light intensity dependence of the photocurrent suggests that the photocurrent arises from the thermal dissociation of the exciton states of the halogen doublet.

Effect of chlorine impurities on the long-wavelength absorption edge of CdTe single crystals

2009 ◽  
Vol 43 (6) ◽  
pp. 730-734 ◽  
Author(s):  
V. D. Popovych ◽  
P. Potera ◽  
I. S. Virt ◽  
M. F. Bilyk
Keyword(s):  
Single Crystals ◽  
Absorption Edge ◽  
Long Wavelength ◽  
Wavelength Absorption ◽  
Effect Of Chlorine

Photocytotoxicity of Anthracyclines upon Laser Excitation in Their Long-Wavelength Absorption Bands

1991 ◽  
Vol 127 (1) ◽  
pp. 24 ◽  
Author(s):  
Alessandra Andreoni ◽  
Alberto Colasanti ◽  
Vincenzo Malatesta ◽  
Giuseppe Roberti
Keyword(s):  
Laser Excitation ◽  
Absorption Bands ◽  
Long Wavelength ◽  
Wavelength Absorption

TEMPERATURE-DEPENDENCE OF PROTON CONDUCTIVITY IN HYDROGEN-BONDED MOLECULAR SYSTEMS

2007 ◽  
Vol 21 (19) ◽  
pp. 1239-1252 ◽  
Author(s):  
XIAO-FENG PANG ◽  
BO DENG ◽  
HUAI-WU ZHANG ◽  
YUAN-PING FENG
Keyword(s):  
Experimental Data ◽  
Electric Field ◽  
Temperature Dependence ◽  
Electric Conductivity ◽  
Proton Conductivity ◽  
Model System ◽  
Time Dependent ◽  
Molecular Systems ◽  
Damping Effect ◽  
Hydrogen Bonded

The temperature-dependence of proton electric conductivity in hydrogen-bonded molecular systems with damping effect was studied. The time-dependent velocity of proton and its mobility are determined from the Hamiltonian of a model system. The calculated mobility of (3.57–3.76) × 10-6 m 2/ Vs for uniform ice is in agreement with the experimental value of (1 - 10) × 10-2 m 2/ Vs . When the temperature and damping effects of the medium are considered, the mobility is found to depend on the temperature for various electric field values in the system, i.e. the mobility increases initially and reaches a maximum at about 191 K, but decreases subsequently to a minimum at approximately 241 K, and increases again in the range of 150–270 K. This behavior agrees with experimental data of ice.

scholarly journals Softer but stronger? Sulfur SAD with low energy X-rays of 2.7 Å

2014 ◽  
Vol 70 (a1) ◽  
pp. C604-C604
Author(s):  
Dorothee Liebschner ◽  
Naohiro Matsugaki ◽  
Miki Senda ◽  
Yusuke Yamada ◽  
Toshiya Senda
Keyword(s):  
Absorption Edge ◽  
Protein Crystal ◽  
X Rays ◽  
Long Wavelength ◽  
Heavy Atoms ◽  
Statistical Validity ◽  
Experimental Phasing ◽  
Recent Developments ◽  
Long Time ◽  
Anomalous Signal

Single wavelength anomalous diffraction (SAD) is a powerful experimental phasing technique used in macromolecular crystallography (MX). SAD is based on the absorption of X-rays by heavy atoms, which can be either incorporated into the protein (crystal) or naturally present in the structure, such as sulfur or metal ions. In particular, sulfur seems to be an attractive candidate for phasing, because most proteins contain a considerable number of S atoms. However, the K-absorption edge of sulfur is around 5.1 Å wavelength (2.4 keV), which is far from the optimal wavelength of most MX-beamlines at synchrotrons. Therefore, phasing experiments have to be performed further away from the absorption edge, which results in weaker anomalous signal. This explains why S-SAD was not commonly used for a long time, although its feasibility was illustrated by the ground-breaking study by Hendrickson and Teeter [1]. Recent developments in instrumentation, software and methodology made it possible to measure intensities more accurately, and, as a consequence, S-SAD has lately obtained more and more attention [2]. The beamline BL-1A at Photon factory (KEK, Japan) is designed to take full advantage of a long wavelength X-ray beam at around 3 Å to further enhance anomalous signals. We performed S-SAD experiments at BL-1A using two different wavelengths (1.9 Å and 2.7 Å) and compared their phasing capabilities. This methodological study was performed with ferredoxin reductase crystals of various sizes. In order to guarantee statistical validity and to exclude the influence of a particular sample, we repeated the comparison with several crystals. The novelty in the approach consists in using very long wavelengths (2.7 Å), not fully exploited in the literature so far. According to our study, the 2.7 Å wavelength shows - despite strong absorption effects of the diffracted X-rays - more successful phasing results than at 1.9 Å.

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