Dopant sites

L.B. Moran, J.K. Berkowitz, J.P. Yesinowski, F and P magic angle spinning nuclear magnetic resonance of antiomony (III) doped fluorapatite phosphors Dopant sites and spin diffusion, Phys. Rev. B 45 (1992) 5347-5360. 

Dopant site location in core and core-shell nanoparticles... 

In brief, the core-shell technique allows one to prepare doped nanoparticles that contain no other dopant sites than those known from the corresponding bulk material, despite their small size, below 15 nm. The quantum efficiency of lanthanide ions can also be improved by surface modification of the nanoparticles. 

Figure 7.10 Schematic illustration of electron and hole trapping at dopant sites and subsequent donor-acceptor-mediated photon emission. (Adapted from Ozawa and Itoh [33])...

Cr + laser emission has been obtained from a variety of crystals in two very different ways, depending on the strength of the crystal field at the dopant site and whether the emission... 

Polymer light-emitting devices (PLEDs) have attracted considerable interest because of their potential use in portable electronic devices. PLEDs have improved the performance of devices by increasing the device stability and efficiency. Chang and coworkers fabricated an efficient PLED using [Ir(acac)(dbq)2] as the phosphorescent dopant of a pvk matrix layer and bbpo as the electron transport material. Trapping of charge carriers at the [Ir(acac)(dbq)2] dopant sites dominates the EL of the device. This is the first PLED that emits red electrophosphorescence centered at 610 nm, exclusively from the dopant and an EL efficiency of 8.5 cdA (luminance 1287 cdm ) biased at 14.5 mAcm . ... 

Bush, T.S., C.R.A. Catlow, A.V. Chadwick, M. Cole, R.M. Geatches, G.N. Greaves, and S.M. Tomlinson. 1992. Studies of cation dopant sites in metal oxides by EXAFS and computer-simulation techniques. J. Mater. Chem. 2 309-316. 

Davies RA, Islam MS, Chadwick AV, Rush GE (2000) Cation dopant sites in the CaZr03 proton conductor a combined EXAFS and computer simulation study. Sol State Ionics 130 115-122 Davies SN, DeWiest RCM (1966) Hydrogeology. Wiley Sons, New York... 

Moran LB, Berkowitz JK, Yesinowski JP (1992) and P magic-angle spinning nnclear magnetic resonance of antimony (Ill)-doped flnorapatite phosphors Dopant sites and spin diffusion. Phys Rev B 45 5347-5360... 

P (299 cm ) S (382 cm ) Cl (587 cm ) As (1500 cm ). This fact strongly suggests that the charge carriers present very little at the dopant site, in contrast with the alkali dopants in PA [287]. A possible origin of such a contrast would be a difference between acceptor and donor vacant donor levels may be placed nearer to the conduction band than filled acceptor levels. The symmetry restriction on the Elliott mechanism seems not to appear in the heterocyclic polymers. 

The hterature is not yet clear on whether sol-gel synthesis methods can be manipulated in such a manner as to allow aU dopant sites to be accessible, although surface modification of micelletemplated materials (1, 38 10) is an approach that has particular promise in this regard. 

Although they do not present a structure of doped PTh, in their account of their X-ray investigations on the pristine polymer, Bruckner and Porzio describe the diffraction obtained from a CIOJ doped sample. From the similarity of certain peaks to those of the undoped polymer, they conclude that interplanar spacing is not greatly affected by dopants, but from the increased peak widths, they surmised that the CIOJ ions occupy random sites. While this does not necessarily imply intercalation by the anions, the predictions of several dopant sites with similar energies suggests the possibility of random occupations, and... 

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