Results 251 to 260 of about 69,417 (298)

The Si:Er Crystal: Model and Excitation Mechanism of the Er-O Center

Solid State Phenomena, 1995
Abstract Analysing the electronic structure of silicon crystals, both regular and doped with erbium, we conclude that the erbium ion tends to form bonds with three ligands. The role of oxygen in the passivation of the formed dangling bond is discussed.
D.E. Onopko, N.T. Bagraev, A.I. Ryskin
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The Crystal Structure of the Photosynthetic Reaction Center from Rhodopseudomonas viridis

1985
The photosynthetic reaction center (RC) from Rhodopseudomonas viridis (R. viridis) was one of the first integral membrane proteins which could be crystallized (Michel, 1982). The crystals turned out to be suitable for X-ray structure analysis at atomic resolution.
J. Deisenhofer, H. Michel
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Investigation of the homogeneity of trapping centers in photorefractive crystals

Journal of Applied Physics, 1992
The homogeneity of trapping centers in photorefractive crystals has been investigated with a novel method. Phase gratings written in the crystal are read out with a beam that is focused by a cylindrical lens. The diffracted intensity distribution is measured while scanning the focal line of the readout beam over the crystal plate.
P. Amrhein, P. Günter
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Luminescence centers of the blue range in lithium fluoride crystals

AIP Conference Proceedings, 2021
We present results of studies of formation mechanism of luminescence centers of the blue range in lithium fluoride crystals. We found that the centers under study are intrinsic defects of crystal lattice formed as a result of a radiation-thermal process in the temperature range much higher than room temperature.
N. T. Maksimova, V. M. Kostyukov, V. V. Tolstikov   +2 more
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Crystal field of Yb3+ tetragonal centers in the YbRh2Si2 intermetallic compound

Physics of the Solid State, 2007
The spectra of electron paramagnetic resonance and inelastic neutron scattering in crystals of the heavy-fermion intermetallic compound YbRh 2Si2 are interpreted. The phenomenological potentials of the crystal electric field of Yb3+ tetragonal centers and the parameter of the Hamiltonian for the spin-orbit interaction of electrons are determined from ...
Leushin A., Ivanshin V., Kurkin I.
openaire   +3 more sources

On the decay properties of the M′ center in LiF crystals

physica status solidi (b), 1989
AbstractFor the first time properties concerning the luminescence decay time as well as the relative quantum yield of M′ center in LiF X‐ray irradiated samples are simultaneously and accurately investigated as a function of temperature in the range 12.5 to 335 K.
L. Bosi, M. Nimis
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The internal reduction of Ag+ centers in NaCl crystals

Acta Metallurgica, 1971
Abstract If color-centers diffuse into a NaCl-AgCl crystal, the Ag+ ions are reduced and precipitate as colloidal particles of metallic silver. Since this process seems to be quite analogous to the internal oxidation of binary metallic alloys, measurements were made to obtain the number and size of the silver particles vs.
openaire   +1 more source

Kinetics of the alignment of O-2 centers in stressed alkali halide crystals

Solid State Communications, 1966
Abstract A theory of the kinetic properties of the O 2 - center has been developed. The standard perturbation theory is used for the calculation of the orientation and reorientation times. The processes which involve the tunneling of the center, accompanied by the absorption or emission of one and two phonons are considered.
R. Pirc, B. žekš, P. Gosar
openaire   +1 more source

Semi-empirical simulations of the electron centers in MgO crystal

Computational Materials Science, 1996
Abstract Semi-empirical quantum chemical simulations of 125-atom clusters have been undertaken to obtain the self-consistent atomic and electronic structure of the two basic electron defects in MgO crystals — F+ and F centers (one and two electrons trapped by an O vacancy).
R.I. Eglitis, M.M. Kuklja, E.A. Kotomin, A. Stashans, A.I. Popov   +4 more
openaire   +1 more source

Zero phonon lines of the M-center in ZnS crystals

Journal of Luminescence, 1988
Abstract The zero phonon line of the M-center luminescence in ZnS crystals has been detected at 819.76nm. As a consequence of this the entire structure of the M-band could be explained and a sum rule for zero phonon lines in emission and excitation of deep centers in II-VI semiconductors has been derived.
Axel Hoffmann, Immanuel Broser, Peter Thomsen-Schmidt   +2 more
openaire   +1 more source