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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 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 structures and properties of CdSe quantum dots (clusters) are examined by combining experimental absorption, photoluminescence (PL), and X-ray diffraction (XRD) spectroscopies as well as ab initio density functional theory (DFT). The results have shown that the current synthesis scheme using hexadecylamine (HDA) reduced agglomeration of clusters during nucleation and growth, thereby enhancing PHI(sub PL).

A study of the influence of high intensity laser light on the optical properties and exciton relaxation dynamics in CdSe nanocrystals passivated by tri-n-octylphosphine oxide and dispersed in the optically clear poly(butamethacrylate) polymer is reported. The modification of the optical properties of the CdSe/PBMA film is observed after exposure to high intensity laser pulses.

The overall rate coefficients of the reactions of CSe(sub 2), SCSe, and OCSe with O((super 3)P) atom are examined. An excellent match between the decay rate of OCSe with the appearance rate of CO upon O atom reactions is found, which suggest that only a single channel is open while the measured rate coefficient may be used to describe the single reaction, O + OCSe -> CO +SeO.

Experimental results and possible explanations will be presented on how substrate temperature and air annealing influence the interface between Cu(In, Ga)Se2 (CIGS) and powder evaporated In(sub x)S(sub y). These interfaces are studied by means of bright-field and high-resolution transmission electron microscopy.

Charging effects in a CdSe nanotetrapod are theoretically investigated by using an atomistic pseudopotential method. It is found that surface polarization can significantly change the electron wave functions and depending on the situation the tetrapod can behave like a single coherent dot to weakly coupled multiple dots.

Spectroscopic properties and the gain of the 1.6 (mu)m emission un selenide and chalcohalide glasses doped with Ho(super 3+) were investigated. Intense 1.6 (mu)m emission with high quantum efficiency was observed from both glasses.

The Tl4Se8(super 4-), [Tl2Se4(super 2-)]infinity(super 1), and Tl2Se6(super 6-) anions have chain structures comprised of Tl2Se2 rings whereas the Tl3Se6(super 5-) and Tl3Se7(super 5-) anion structures are based on nido-cubes. Theoretical studies confirm that these anions are classically bonded rings and cages.

A systematic study of both shift and injection currents in the wurtzite semiconductors CdSe and CdS at 295 K is generated using above-band-gap femtosecond pulses and detected through the emitted terahertz radiation. The results have shown no temporal difference between the electro-optic (EO) terahertz traces from shift and injection currents in CdS, implying the momentum scattering time in all experiments is less than 100 fs.

The evidence for an interaction between the quantum dot exciton fine structure states F= plusmn1 is obtained by measuring the dynamics of transition among those states, exciton spin relaxation or flipping. The results for colloidal Cdse quantum dots revealed strong size dependence for the exciton spin relaxation, consistent with its origin being attributed to a long-range contribution to the electron-hole exchange interaction.

A comprehensive study was performed on the polar (0001) and (0001) and nonpolar (1120) wurtzite CdSe surfaces that are exposed during crystal growth using first-principles density functional theory calculations. Stabilization of these surfaces by relaxation and reconstruction was considered.

An electron microscopic observation of crystal shape development when PbSe nanocrystals were synthesized using a dynamic injection technique at different temperatures in the presence of oleic acid is presented. A two-step evolution mechanism is proposed, indicating that the shape evolution of PbSe nanocrystals is dependent on the growth time, whereas the crystalline size can be tuned by varying the growth temperature under the studied conditions.

Optically active seleninate esters are obtained by chromatographic resolution on an optically active column. The reaction of the optically active seleninate ester and the sulfinate ester having bulky substituents with Grignard reagents is found to proceed with the retention of stereochemistry to give an optically active selenoxide and sulfoxides, respectively.

The synthetic routes to salts of the 3H-naphthol[1,2-d][1,2,3]dithiazolylium cation and its three selenium-containing variants (SSeN, SeSN, and SeSeN) are described. The most efficient and general method involves the intermediacy of bis-acetylated aminothiolates and aminoselenolates.

The potential of the X-ray powder diffraction (XRPD) technique for direct structural characterization of insoluble coordination polymers that resist single-crystal growth techniques is illustrated. The crystal structures of two building blocks, [Rh2(O2CCH3)(sub 4)] and Se2C5H8, and of the hybrid coordination product are presented.

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.

The three-dimensional structure of oleic acid-capped CdSe and thiol-capped CdTe nanocrystals used as quantum dots is determined by total synchrotron radiation x-ray diffraction and atomic pair distribution functional analysis. The results have shown that both CdSe and CdTe have displayed the zinc-blende-type atomic ordering.

Avidin-biotin conjugation is used to create rod dimers, trimers, and flowers based on linking through the gold tips of the nanodumbbells (NDBs). This has established the use of such tips as anchor tips for self-assembly.

The photoinduced charge transfer (CT) between CdSe nanocrystal quantum dots (NQDs) and a series of Ru-polypyridine complexes in solution are studied. It is shown that mixing of NQDs and Ru-polypyridine complexes results in formation of electronically coupled assemblies and the photoexcitation of these assemblies has led to the oxidation of the adsorbed complex through efficient hole transfer from the NQD.

Modulation of the interparticle electron transfer rate is reported by varying the QD particle size. The transient absorption measurements demonstrate the possibility of modulating the electron transfer rate between CdSe and Ti[O.sub.2] particles by making use of size quantization effects.

Radovanovic and Gamelin demonstrate a strategy similar to the growth doping to solve the unfavorable incorporation of CO(super +) in CdS nanocrystals. Using copper-doped ZnSe as the model system successful doping and decoupling of doping from possible nucleation and growth are indicated by several facts.

A study demonstrates that combining Tb(super 3+) with CdSe semiconductor nanocrystals (SCNCs) creates an advantageous new type of lanthanide-based luminescent material. Results validate the proposed approach for synthesizing CdSe:Tb SCNCs with the electronic structure of the nanocrystals serving as an antenna for the lanthanide cation.