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High-speed imaging applications, such as time-resolved X-ray diffraction, require detectors with high frame rates ranging from hundreds to thousands of frames per second. New high-resolution CCD imagers capable of operating at the required frame rates have been developed; however, the current X-ray to light converters are the performance limiting factor in such applications. Here we report on the development of a structured ZnSe:Te scintillator that promises to provide extraordinarily high scintillation efficiency, emission at 640 nm (ideally suited for CCD sensors), high density of 5.4 g/[cm.sup.3], and a fast decay time of ~ 3 [micro]s to ~ 50 [micro]s with no afterglow, which permits high speed imaging without the problem of ghosting due to persistence. Furthermore, the non-hygroscopic and non-toxic nature of the ZnSe:Te scintillator, along with its stability of response over a wide range of temperatures and extremely high levels of radiation, makes it an ideal material for radiation detection in general and for synchrotron applications in particular. At RMD, we have fabricated microcolumnar ZnSe:Te films measuring ~ 25 [micro]in to 85 [micro]m in thickness using co-evaporation of ZnSe and ZnTe on suitable substrates. These films show columnar structure with columns ranging from 0.2 [micro]m to 5 [micro]m in diameter. The scintillation light produced by the radiation interaction is channeled within the microcolumns by the mechanism of total internal reflection, thereby providing very high spatial resolution, even when films are made thick to achieve high X-ray absorption. Index Terms--Bright scintillator, high-speed imaging, low after glow scintillator, microcolumnar zinc selenide.

Large volume zinc tungstate crystal scintillators (up to 50 mm in diameter and 100 mm length) with improved energy resolution were developed as result of advances in crystal growth. The energy resolution of one-centimeter cube ZnW[O.sub.4] crystals showed energy resolution in the range 8-10% for 662 keV [gamma] line of [sup.137]Cs. A value of 13.7% has been obtained with a large sample [empty set] 44 x 55 mm. The radioactive contamination of a ZnW[O.sub.4] 26 X 24 x 24 mm detector was tested in the Solotvina Underground Laboratory. The obtained results demonstrate ability to use ZnW[O.sub.4] in order to search for 2[beta]-decay of Zinc and Tungsten. Index Terms--Double beta decay, scintillation detectors, tungsten compounds, zinc compounds.

A high light yield at low temperatures is one of the key criteria in the choice of scintillating target crystals for the CRESST-II Dark Matter search. We perform a feasibility study on ZnW[O.sub.4] crystals as scintillating targets for the CRESST-II experiment. The light yield and the quenching factors of ZnW[O.sub.4] at mK temperatures are given for the first time. Index Terms--Dark matter, light yield, low temperature detectors, quenching factor, silicon radiation detector, superconducting films, zinc tungstate.

Energy resolution and detection efficiency were compared between new scintillators, Lanthanum Bromide (La[Br.sub.3] : Ce) and Lanthanum Chloride (La[Cl.sub.3] : Ce) with conventional detectors, Sodium Iodide (NaI(T1) and Cadmium Zinc Telluride (CdZnTe or CZT). The study has shown that La[Br.sub.3] : Ce and La[Cl.sub.3] : Ce scintillator detectors provided by Saint-Gobain offer better resolution than NaI(TI) detector. La[Br.sub.3] : Ce and La[Cl.sub.3] : Ce detectors could resolve some closely spaced peaks from [sup.133]Ba and [sup.152]Eu, which Na(I) could not. La[Br.sub.3] : Ce has slightly better resolution and higher efficiency than La[Cl.sub.3] : Ce. An overall advantage of La[Br.sub.3] : Ce and La[Cl.sub.3] : Ce detectors over NaI(T1) and CZT has been discussed. The intrinsic activity of La[Br.sub.3] : Ce is also demonstrated in this study. Index Terms--CZT, efficiency, gamma spectral comparison, La[Br.sub.3] : Ce, La[Cl.sub.3] : Ce, NaI(T1), resolution.

The effect of the electron beam of the microscope on the crystallization process of phase change materials was investigated. A continuous increase in the crystal growth velocity was found due to electron irradiation during the crystallization process.

The crystal structures, atomic distributions, and theoretical electronic structures of a series of [Cu.sub.5-x][Zn.sub.8+x] compounds (x = -0.59, -0.31, 0.00, 0.44, and 0.79) with the [gamma]-brass structure are reported with the goal of identifying chemical influences on the observed phase width. In all cases, the 26-atom cluster building up the [gamma]-brass structure shows a constant inner [[Cu.sub.4][Zn.sub.4]] tetrahedral star with compositional variation occurring at the outer octahedron and cuboctahedron.

Photon statistics of blinking CdSe-ZnS nanocrystals interacting with a continuous wave laser field is analyzed showing that the process is described by a ballistic Levy walk. It is shown that Mandels Q parameter, describing the fluctuations of the photon counts is increasing with time eve in the limit of long time.

The alloy nanowires of [Zn.sub.x][Cd.sub.1-x]Se with composition x=0,0.2,0.5,0.7 and 1 were successfully synthesized by a chemical vapor deposition (CVD) method assisted with laser ablation. The [Zn.sub.x][Cd.sub.1-x]Se nanowires were found to be single crystalline and can serve as important integrated full-color display elements in optical and sensory nanotechnological applications.

The synthesis and two photon-induced absorption (TPA) properties of a functionalized distyrylbenzene (DSB) containing a tetra-azacyclododecane (cyclen) receptor for Zn(II) are presented. The experiments show that the TPA action spectrum of uncomplexed distrylbenzene, at 750 nm employing nanosecond-long excitation pulses, is 5 times more intense than that of the complexed form.

The characterization of an electrochemically created Pt/Zn alloy by electron spectroscopy is presented indicating the formation, oxidation of alloy and the room temperature diffusion of the Zn into Pt regions. The Pt./Zn alloy is stable up to 1.2 V/RHE and could only be removed with the oxidation of the base Pt metal either electrochemically or in aqua regia.

First-principles calculations were performed to examine the migration of Li(super plus) ions through the vacancy mechanism in lithium halides with the rocksalt and hypothetical zinc blende structures and lithium chalcogenides with the antifluorite structure. The findings show a migration path similar to that in the charged-sphere model, indicating that electrostatic attractive interactions play a dominant role in the inter-ion interactions in Li(sub 2)O and, therdefore, in the ion migration.

The efficacy of diffusing cobalt into window-grade polycrystalline ZnSe during high-temperature anneals is studied. Absorption, photoluminescence (PL), time-resolved PL, and electron paramagnetic resonance (EPR) are used to characterize samples with cobalt concentrations ranging from 10(super17) to 10(super19) cm(super -3).

The chemical and electronic properties of tin-doped indium oxide (ITO) surfaces and its interface with zinc phthalocyanine (ZnPc) are examined using photoelectron spectroscopy partly excited by synchrotron radiation from the BESSY II storage ring. It is demonstrated that ITO surfaces can display large Fermi level shifts depending on substrate preparation.

The first magnesium and zinc boraamidinate (bam) complexes are synthesized via metathetical reactions between dilithio atoms and Grignard reagents or MCl2 (M=Mg, Zn). The results show that the bam anionic radical [PhB(N(super t)Bu)(sub 2)](super .-) can be stabilized by coordination to a variety of early main-group metal centers to provide neutral radicals whose relative stabilities are compared and discussed.

Zinc selenide, cadmium sulfide, and cadmium selenide clusters were produced by direct laser ablation and in a time-of-flight mass spectrometer is analyzed. The relative stability of the positive stoichiometric clusters provides a thermodynamic explanation for the relative stability observed experimentally from the laser-ablation mass spectrometry.

The singlet-singlet annihilation within the series of Zn-porphyrin dendrimers by means of intensity dependent transient absorption experiments is studied. Analysis showed that sequential annihilation occurs within subunits up to four Zn-porphyrins in the dendrimers, and a full characterization of the transient absorption kinetics of the monomer over a spectral range from 450 to 730 nm is reported.

Vacataporphyrin, which belongs to the family of core-modified porphyrins and resembles the parent 5, 10, 15, 20 tetaarylporphyrin, reveals interesting properties as a ligand. The molecule coordinates through three nitrogen atoms and due to coordination the macrocycle acquires two fundamentally different conformations affording, eventually, different modes of weak transaction between the central metal ion and the butadiene fragment.

The formation and structural characteristics of Ru species applied as a cocatalyst on (Ga(sub 1-x)Zn(sub x))(N(sub 1-x)O(sub x)) were examined by scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray absorption spectroscopy. Calcination was shown to cause the decomposition of initial Ru3(CO)12 on the (Ga(sub 1-x)Zn(sub x))(N(sub 1-x)O(sub x)) surface to form Ru(IV) species.

The (super 29)Si, (super 27)Al and (super 67)Zn NMR evidence is presented to show that silicate ions in alkaline solution form complexes with zinc(II) and concomitantly, with aluminate (Al(OH)(sub 4) (super -)). Zincate reacts with monomeric silicate at pH 14-15 to from [(HO)O2Si-O-Zn(OH)3](super 4-) and with dimeric silicate to produce [HO-SiO2-O-SiO2-O-Zn(OH)3](super 6-).

The study was conducted to know the effect of metal substitution on the activity and structure of the aminopeptidase P (APPro) from Escherichia coli. The result reveals that excess Zn presence demonstrates a third party metal-binding site, formed by two conserved His residues and the dipeptide inhibitor and Zn atom bound at such a site would stabilize product binding and enhance inhibition.

A detailed investigation of the temperature dependence of the edge excitonic transitions of three Bridgman-grown wurtzite-type Cd(sub 1-x-y)Be(sub x)Zn(sub y)Se-mixed crystals is conducted. The parameters that describe the temperature dependence of the interband transition energies and the broadening function of the excitonic features are evaluated and discussed.

Absorption, photoluminescence, and time-resolved photoluminescence spectroscopies are used to study the properties of polycrystalline ZnSe diffusion doped with Fe or Co or codoped with both Fe and Co. Energy transfer between Co(super 2+) and Fe(super 2+) ions gives rise to modified behaviors of optical transitions near 3 mum.

A new technique employed to study the photophysical properties of the zinc(II) tetraphenylporphine cation radical is reported. It employs a combination of controlled potential coulometry and femtosecond absorption spectrometry.

The reaction of zinc and cadmium atoms (Zn and Cd) with O2 + H2 in solid argon and neon is reported. The results revealed that laser-ablated zinc and cadmium atoms were deposited with H2 and O2 in excess argon or neon and with O2 in pure hydrogen or deutrium during deposition at 8 or 4 K.

The ground states of small, nonstoichiometric zinc clusters Zn(sub n)S(sub m) and Zn(sub n)S(sub m)(super +) were studied using density functional theory. Results reveal that sulfur-sulfur bonding in larger ZnS clusters could be feasible without significant energetic cost and that such structures should be considered.

The refractive indices for cubic-phase thin alloys are determined from transmission measurements and Manifacier envelope method. The refractive index of dispersion relation of cubic Mg(sub x)Zn(sub 1-x)O in the visible light region follows the first-order Sellmeier equation and decreases with the increase of Mg fraction.

Directly meso-meso linked porphyrin rings that respectively comprise four, six, and eight porphyrins are synthesized in a stepwise manner from a 5,10-diaryl zinc(II) porphyrin building block. These porphyrin rings serve as a well-defined wheel-shaped light harvesting antenna model in light of very efficient excitation energy hopping along the ring.

Confocal Raman microscopy was used to observe potential dependent surface-enhanced Raman spectra (SERS) of pyridine adsorbed on a bare zinc (Zn) bulk electrode, and adsorption behavior of pyridine on zinc. Related SEM measurement was performed to obtain the morphological information of the roughened electrode for understanding the SERS mechanism on it.

The structures and electroluminiscent properties of bis2-(2-hydroxyphenyyl)benzothiazolate are investigated. The molecular structure of an anhydrous [Zn(BTZ)(sub 2)](sub 2) obtained by sublimation is determined by X-ray single-crystal diffraction.

The pressure dependence of Mn(super 2+) emission in the 10-, 4.5-, 3.5-, 3-, and 1-nm-sized ZnS:Mn(super 2+) nanoparticles is investigated where the emission shifts to lower energies with increasing pressure, and the shift rate is larger in the ZnS:Mn(super 2+) nanoparticles than in bulk. These new observations are helpful for understanding the luminescence mechanisms in doped nanoparticles.

The location of the [ZnOZn](Super 2+) cluster in zeolites was studied by the periodic al density functional method for a chosen composition of two Si atoms substituted by two Al atoms in the same D6R unit cell of the chabazite framework. In the case of the six-membered ring the stability is markedly influenced by the electrostatic interaction due to the close proximity oft the Zn cations to the ring plane.

The proton spin relaxation induced by the triplet ground state of oxygen in the zinc containing diamagnetic analogue of sperm whale deoxymyoglobin is demonstrated. The relaxation effects at the amide proton sites are found to be highly localized and are derived almost exclusively from O2 binding at the four previously identified xenon-binding sites.

The examination of tris(pyrazolyl)hydroborato zinc complexes by low-temperature solid-state (super 67)zinc Nuclear Magnetic Resonance spectroscopy is reported. The main aim of the examination is to understand the chemistry of zinc and the associated biological importance of that chemistry.

Monolayers of zinc porphyrin trimers on graphite by liquid-phase deposition are prepared and imaged the molecular films with bond atomic force microscopy (AFM) and scanning tunneling microscopy (STM). It provides a useful platform for the study of surface and interface phenomena outside a vacuum system and is potentially useful for practical fabrication of molecular devices.

A detailed study by time-resolved fluorescence that more thoroughly characterizes the energy transfer and light-collecting properties of these units applying various donors and acceptor pairs are presented. The result reveals that these units have suitable properties as artificial antenna systems for solar energy utilization.

Density functional theory (DFT) at B3LYP level of method with adequate atomic basis sets are employed to analyze the ionization potential, the geometries and bond energies of zincate complexes arising from ZnO, Zn-OH and ZnO-H2O species. Analysis revealed that zincate species like [Zn(OH)](super +), Zn(OH)2 and [Zn(OH)3](super -) complex are stable in gas phase.

The photoinduced energy transfer processes in 1,4-phenylene, 1,3-phenylene, 1,2-phenylene, and 4,4'-bi-phenylene-linked and directly-linked zinc(II) free-base porphyrins heterodimers in THF were investigated by femtosecond transient absorption spectroscopy. The results indicate that even for the covalently-linked models the relative contribution of the through-space Coulombic interaction becomes increasingly important upon the decrease of the center-to-center separation.

The coordination on a neutral boronate bridge allows a convenient method of controlling intransmolecular electron transfer (ET). The intramolecular ET reaction from zinc-porphyrin to diimide acceptor through the boronate-bridge is suppressed by the F-coordination on the boron atom.

The syntheses and molecular structures of a series of tetrahedral zinc complexes designed to model the active sites in Escherichia coli methionine synthases are described. The tridentate ligands provide the appropriate donor atoms, [S3] and [S2N], to accurately model the catalytic zinc sites in the methionine synthases from E. coli.

The phosphatidylcholine-preferring phospholipase C from Bacillus cereus is inhibited by the cyclic N,N' -dihydroxyureas 6-10. This class of inhibitors is thought to function by the bidentate chelation of the N,N' -dihydroxyurea array to one or more of the zinc ions at the active site of the enzymes.

An optical microscopy study on the domain structures of 0.955Pb(Zn(sub 1/3)Nb(sub 2/3))O3-0.045PbTiO3 rhombohedral phase single crystals poled along [001] of the cubic coordinates is reported. The study showed that the domain patterns in the domain engineered PZN-4.5%PT single crystals are predominantly twins containing only two of the four possible domains after being poled in [001].

Strategies of both self-assembly and metal ion replacement are adopted in the development of metal ion sensors for Zn(super 2+) and Hg(super 2+). 1,4-bis{[3-ethyl-4-methyl-5-[(ethyloxy)carbonyl]pyrrol-2-yl]methyleneamine}benzene could be a good Zn(super 2+) sensor candidate based on the mechanisms of the chelation-enhanced fluorescence effect and the replacement of central metal ion induced chelation-enhanced fluorescence quenching effect, respectively.

Zn3N2 polycrystalline films with n(super +)-type conductivity are grown by metalorganic chemical vapor deposition and rf-molecular beam epitaxy with carrier concentration in the range between 10(super19)and ~10(super 20) cm(super-3). Oxygen contamination without an intentional doing is found to be a cause of high electron concentration, leading to larger band-gap energy due to Burstein-Moss shift.

Terahertz is observed from (100) Zn-acceptor-doped InAs under illumination by fs pulses of near-infrared radiation. The emitted terahertz powder has a quadratic variation with the pump power and decreases with increasing temperature.

The first discrete, selenium-centered tetranuclear zinc cluster [Zn4(super -)u4-Se){Se2P(OPr)2}6] was isolated and characterized. The cluster consisted of six edge-bridged dsep ligands with four zinc atoms in a slightly distorted tetrahedron and u4-Se atom in the center.

Density functional theory is used to study the structural, electronic and optical properties of oxygen-defective [Zn.sub.3][N.sub.2]. The results have shown that [Zn.sub.3][N.sub.2] with nitrogen replaced by oxygen is more stable than that with interstitial oxygen and substitutional oxygen for nitrogen in defective [Zn.sub.3][N.sub.2] is responsible for the n-type conduction character.

The synthetic and structural studies of metal-organic framework materials in the zinc sulfite composition are reported. The results have shown that [Zn.sup.2+] and S[O.sub.3.sup.2-] can form various inorganic subunits that can be zero-dimensional (0-D) clusters, one-dimensional (1-D) chains or two-dimensional (2-D) sheets.

Nanocrystalline ZnS was coarsened under hydrothermal conditions to investigate the effect of particle size on phase transformation kinetics. A new phase transformation kinetic model was developed based on collective movement of atoms across the interface.

The Dynamic Jahn-Teller effect in the near-infrared spectra of Fe(super 2+) ions in ZnS is examined. Results indicate a significant charge transfer in ZnS:Fe(super 2+).

Using time-integrated and spectrally resolved four wave mixing (FWM) the impact of k-linear term on C-exciton manifold in ZnO is studied experimentally. The result of spectral decomposition analysis is highlighted.