Specular reflection and absorption edges of xenon difluoride single crystals in the near ultraviolet

Single crystals of the perylene–fluoranil charge-transfer complex were found to be photoconductive throughout the near ultraviolet, visible, and near infrared spectral regions. The temperature dependence of the semiconduction and photoconduction are characterized by apparent activation energies of 0.73 ev and 0.12 ev, respectively. Conductivity parallel to the c-crystallographic axis (along which the complex units are stacked in columns) was found to be about threefold greater than that in the perpendicular direction. Attempts to measure carrier mobilities proved unsuccessful. The results suggest extrinsic carrier generation accompanied by pronounced carrier trapping processes.

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THE ELECTRONIC SPECTRA OF CRYSTALLINE TOLUENE, DIBENZYL, DIPHENYLMETHANE, AND BIPHENYL IN THE NEAR ULTRAVIOLET

Canadian Journal of Chemistry ◽

10.1139/v58-006 ◽

1958 ◽

Vol 36 (1) ◽

pp. 48-58 ◽

Cited By ~ 60

Author(s):

Robert Coffman ◽

Donald S. McClure

Keyword(s):

Single Crystals ◽

Excited States ◽

Electronic Absorption ◽

Electronic Spectra ◽

Weak Coupling ◽

Electronic Absorption Spectra ◽

Polarized Light ◽

Near Ultraviolet ◽

Benzene Rings ◽

First Time

The electronic absorption spectra of single crystals of toluene, dibenzyl, diphenylmethane, and biphenyl have been photographed at 20 °K. using polarized light in the range 3000 to 2500 Å. The fluorescence spectrum of biphenyl has also been examined. This is the first time that the excited states of biphenyl analogous to the B2u state of benzene have been observed. The main features of the spectra are similar for all four compounds, and the differences may be understood in terms of the weak coupling between the benzene rings of the "double molecules".

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Absorption Edges of KCl Single Crystals

Journal of the Physical Society of Japan ◽

10.1143/jpsj.21.403 ◽

1966 ◽

Vol 21 (2) ◽

pp. 403-404 ◽

Cited By ~ 6

Author(s):

Tetsuhiko Tomiki

Keyword(s):

Single Crystals ◽

Absorption Edges

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Transverse conduction electron focusing and specular reflection in aluminium single crystals

Journal of Physics F Metal Physics ◽

10.1088/0305-4608/16/12/016 ◽

1986 ◽

Vol 16 (12) ◽

pp. 2053-2062 ◽

Cited By ~ 5

Author(s):

H Sato ◽

K Yonemitsu

Keyword(s):

Single Crystals ◽

Conduction Electron ◽

Specular Reflection ◽

Electron Focusing

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Extended Hückel molecular orbital calculations on some titanium–oxygen systems

Canadian Journal of Chemistry ◽

10.1139/v68-439 ◽

1968 ◽

Vol 46 (16) ◽

pp. 2667-2674 ◽

Cited By ~ 6

Author(s):

Yu-Ping Hsia

Keyword(s):

Molecular Orbital ◽

Energy Levels ◽

Molecular Orbital Calculations ◽

X Ray ◽

Near Ultraviolet ◽

Extended Hückel ◽

Self Consistent ◽

X Ray Absorption ◽

Tetragonal Batio ◽

Absorption Edges

Extended Hückel molecular orbital calculations have been performed on localized TiO68− units with the precise geometry of such a unit in solid rutile, anatase, and brookite TiO2 and tetragonal BaTiO3. The relative values of one-electron energy levels in these compounds are obtained in terms of a "self-consistent" charge and population calculation. Examination of the resulting energy levels and charge distributions has led to reasonable explanations of previously unexplained data on (1) the visible and near-ultraviolet absorption spectra of these compounds, (2) the low energy X-ray absorption edges of rutile, anatase, and brookite TiO2, and (3) the pressure dependence of the absorption edges of rutile TiO2 and tetragonal BaTiO3.

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The Electronic Single Crystal Spectrum of Binuclear Rhodium(II)acetate Hydrate Rh2(CH3COO)4· 2 H2O

Zeitschrift für Naturforschung B ◽

10.1515/znb-1978-1009 ◽

1978 ◽

Vol 33 (10) ◽

pp. 1095-1098 ◽

Cited By ~ 5

Author(s):

G. Bienek ◽

W. Tuszynski ◽

G. Gliemann

Keyword(s):

Single Crystal ◽

Single Crystals ◽

Energy Band ◽

Lower Energy ◽

Ultraviolet Spectrum ◽

Temperature Range ◽

Lower Energy Band ◽

Near Ultraviolet ◽

Temperature Dependences ◽

Acetate Hydrate

Abstract The visible and near-ultraviolet spectrum of rhodium(II)acetate hydrate single crystals has been measured in a temperature range from 10 K to 295 K. Two band systems centered at 17,000 cm-1 and 22,000 cm-1 have been found, both consisting of components polarized parallel to and perpendicular to the rhodium-rhodium z-axis. Polarizations, intensities and temperature dependences are consistent with an assignment of z-polarized a1g →a2u and xy-polarized eg →a2u transitions for the lower energy band. For the higher energy band it could not be determined definitely whether only the b2g →-b1u and eg → b1u transitions give rise to the z-and x,y-polarization directions, respectively, or if b1g → b2u and eg →b2u also make a contribution.

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Electronic structure and fundamental absorption edges of KPb2Br5, K0.5Rb0.5Pb2Br5, and RbPb2Br5 single crystals

Journal of Physics and Chemistry of Solids ◽

10.1016/j.jpcs.2012.01.014 ◽

2012 ◽

Vol 73 (5) ◽

pp. 674-682 ◽

Cited By ~ 70

Author(s):

A.Yu. Tarasova ◽

L.I. Isaenko ◽

V.G. Kesler ◽

V.M. Pashkov ◽

A.P. Yelisseyev ◽

...

Keyword(s):

Electronic Structure ◽

Single Crystals ◽

Absorption Edges

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The Microstructure of Shock-Synthesized Diamond

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006163x ◽

1967 ◽

Vol 25 ◽

pp. 324-325

Author(s):

Lucien F. Trueb

Keyword(s):

Single Crystals ◽

Preferred Orientation ◽

High Magnification ◽

Texture Pattern ◽

Shock Process ◽

New Type ◽

Diffraction Diagram

A new type of synthetic industrial diamond formed by an explosive shock process has been recently developed by the Du Pont Company. This material consists of a mixture of two basically different forms, as shown in Figure 1: relatively flat and compact aggregates of acicular crystallites, and single crystals in the form of irregular polyhedra with straight edges.Figure 2 is a high magnification micrograph typical for the fibrous aggregates; it shows that they are composed of bundles of crystallites 0.05-0.3 μ long and 0.02 μ. wide. The selected area diffraction diagram (insert in Figure 2) consists of a weak polycrystalline ring pattern and a strong texture pattern with arc reflections. The latter results from crystals having preferred orientation, which shows that in a given particle most fibrils have a similar orientation.

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A New Defect in Polyethylene Single Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070795 ◽

1973 ◽

Vol 31 ◽

pp. 70-71

Author(s):

E. L. Thomas ◽

S. L. Sass

Keyword(s):

Single Crystals ◽

Screw Dislocation ◽

Small Distance ◽

Dipole Model ◽

Dislocation Dipole ◽

Chain Folding ◽

Black And White ◽

Polymer Crystal ◽

Different Types

In polyethylene single crystals pairs of black and white lines spaced 700-3,000Å apart, parallel to the [100] and [010] directions, have been identified as microsector boundaries. A microsector is formed when the plane of chain folding changes over a small distance within a polymer crystal. In order for the different types of folds to accommodate at the boundary between the 2 fold domains, a staggering along the chain direction and a rotation of the chains in the plane of the boundary occurs. The black-white contrast from a microsector boundary can be explained in terms of these chain rotations. We demonstrate that microsectors can terminate within the crystal and interpret the observed terminal strain contrast in terms of a screw dislocation dipole model.

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